Mathbench

3. Straight lines

The gradient of the line through two points, and the equation that follows from it. Set for OMPT-A, OMPT-B, OMPT-C, OMPT-D, OMPT-E, OMPT-F and OMPT-G.

All OMPT worksheets


Questions

Sheet length
1

Give the gradient of the line through A(7; 2)A(7;\ -2) and B(11; 4)B(11;\ -4).

Answer:

2

Solve for xx: 5(x2)=2x75\left(x - 2\right) = 2 x - 7

Answer:

3

Solve for xx: x+55=x+46\dfrac{x + 5}{5} = \dfrac{x + 4}{6}

Answer:

4

Give the gradient of the line through A(8; 4)A(8;\ 4) and B(6; 7)B(6;\ 7).

Answer:

5

Solve for xx: 6(x+8)=5x+36\left(x + 8\right) = 5 x + 3

Answer:

6

Solve for xx: x64=x36\dfrac{x - 6}{4} = \dfrac{x - 3}{6}

Answer:

7

Give the gradient of the line through A(7; 1)A(7;\ -1) and B(6; 2)B(6;\ 2).

Answer:

8

Solve for xx: 2(x+5)=6x+92\left(x + 5\right) = 6 x + 9

Answer:

9

Solve for xx: x72=x+36\dfrac{x - 7}{2} = \dfrac{x + 3}{6}

Answer:

10

Give the gradient of the line through A(8; 6)A(-8;\ -6) and B(12; 5)B(-12;\ -5).

Answer:

11

Solve for xx: 7(x4)=4x57\left(x - 4\right) = 4 x - 5

Answer:

12

Solve for xx: x+32=x+54\dfrac{x + 3}{2} = \dfrac{x + 5}{4}

Answer:

13

Give the gradient of the line through A(2; 7)A(2;\ 7) and B(1; 2)B(-1;\ -2).

Answer:

14

Solve for xx: 3(x5)=5x+63\left(x - 5\right) = 5 x + 6

Answer:

15

Solve for xx: x+45=x62\dfrac{x + 4}{5} = \dfrac{x - 6}{2}

Answer:

16

Give the gradient of the line through A(5; 2)A(-5;\ -2) and B(3; 9)B(-3;\ -9).

Answer:

17

Solve for xx: 5(x5)=6x35\left(x - 5\right) = 6 x - 3

Answer:

18

Solve for xx: x+43=x96\dfrac{x + 4}{3} = \dfrac{x - 9}{6}

Answer:

19

Give the gradient of the line through A(5; 2)A(-5;\ 2) and B(2; 0)B(-2;\ 0).

Answer:

20

Solve for xx: 5(x5)=6x45\left(x - 5\right) = 6 x - 4

Answer:

21

Solve for xx: x53=x12\dfrac{x - 5}{3} = \dfrac{x - 1}{2}

Answer:

22

Give the gradient of the line through A(1; 5)A(-1;\ -5) and B(0; 7)B(0;\ -7).

Answer:

23

Solve for xx: 7(x+6)=6x47\left(x + 6\right) = 6 x - 4

Answer:

24

Solve for xx: x+92=x46\dfrac{x + 9}{2} = \dfrac{x - 4}{6}

Answer:

25

Give the gradient of the line through A(5; 2)A(5;\ 2) and B(6; 6)B(6;\ -6).

Answer:

26

Solve for xx: 5(x+8)=3x+25\left(x + 8\right) = 3 x + 2

Answer:

27

Solve for xx: x+96=x45\dfrac{x + 9}{6} = \dfrac{x - 4}{5}

Answer:

28

Give the gradient of the line through A(4; 2)A(-4;\ 2) and B(7; 7)B(-7;\ 7).

Answer:

29

Solve for xx: 2(x5)=6x82\left(x - 5\right) = 6 x - 8

Answer:

30

Solve for xx: x94=x33\dfrac{x - 9}{4} = \dfrac{x - 3}{3}

Answer:

Answers

Every answer below was re-derived independently before this page was built.

1

Answer: 12- \frac{1}{2}

m=y2y1x2x1=4(2)11(7)=12m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{-4 - (-2)}{11 - (7)} = - \frac{1}{2}.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 2-2
  • Subtracted the coordinates in opposite orders → 12\frac{1}{2}
2

Answer: 11

Expand the bracket: 5x10=2x75 x - 10 = 2 x - 7. Collect the xx terms on one side and the numbers on the other, then divide: x=1x = 1.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 53- \frac{5}{3}
  • Moved a term across without changing its sign → 88
3

Answer: 10-10

Cross-multiply to clear both denominators: 6(x+5)=5(x+4)6\left(x + 5\right) = 5\left(x + 4\right). Expand, collect the xx terms and divide: x=10x = -10.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 26-26
  • Added the fractions instead of cross-multiplying → 5011- \frac{50}{11}
4

Answer: 32- \frac{3}{2}

m=y2y1x2x1=7(4)6(8)=32m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{7 - (4)}{6 - (8)} = - \frac{3}{2}.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 23- \frac{2}{3}
  • Subtracted the coordinates in opposite orders → 32\frac{3}{2}
5

Answer: 45-45

Expand the bracket: 6x+48=5x+36 x + 48 = 5 x + 3. Collect the xx terms on one side and the numbers on the other, then divide: x=45x = -45.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 5-5
  • Moved a term across without changing its sign → 54-54
6

Answer: 1212

Cross-multiply to clear both denominators: 6(x6)=4(x3)6\left(x - 6\right) = 4\left(x - 3\right). Expand, collect the xx terms and divide: x=12x = 12.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 332\frac{33}{2}
  • Added the fractions instead of cross-multiplying → 245\frac{24}{5}
7

Answer: 3-3

m=y2y1x2x1=2(1)6(7)=3m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{2 - (-1)}{6 - (7)} = -3.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 13- \frac{1}{3}
  • Subtracted the coordinates in opposite orders → 33
8

Answer: 14\frac{1}{4}

Expand the bracket: 2x+10=6x+92 x + 10 = 6 x + 9. Collect the xx terms on one side and the numbers on the other, then divide: x=14x = \frac{1}{4}.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 1-1
  • Moved a term across without changing its sign → 77
9

Answer: 1212

Cross-multiply to clear both denominators: 6(x7)=2(x+3)6\left(x - 7\right) = 2\left(x + 3\right). Expand, collect the xx terms and divide: x=12x = 12.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 454\frac{45}{4}
  • Added the fractions instead of cross-multiplying → 92\frac{9}{2}
10

Answer: 14- \frac{1}{4}

m=y2y1x2x1=5(6)12(8)=14m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{-5 - (-6)}{-12 - (-8)} = - \frac{1}{4}.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 4-4
  • Subtracted the coordinates in opposite orders → 14\frac{1}{4}
11

Answer: 233\frac{23}{3}

Expand the bracket: 7x28=4x57 x - 28 = 4 x - 5. Collect the xx terms on one side and the numbers on the other, then divide: x=233x = \frac{23}{3}.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 13- \frac{1}{3}
  • Moved a term across without changing its sign → 383\frac{38}{3}
12

Answer: 1-1

Cross-multiply to clear both denominators: 4(x+3)=2(x+5)4\left(x + 3\right) = 2\left(x + 5\right). Expand, collect the xx terms and divide: x=1x = -1.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 72- \frac{7}{2}
  • Added the fractions instead of cross-multiplying → 113- \frac{11}{3}
13

Answer: 33

m=y2y1x2x1=2(7)1(2)=3m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{-2 - (7)}{-1 - (2)} = 3.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 13\frac{1}{3}
  • Subtracted the coordinates in opposite orders → 3-3
14

Answer: 212- \frac{21}{2}

Expand the bracket: 3x15=5x+63 x - 15 = 5 x + 6. Collect the xx terms on one side and the numbers on the other, then divide: x=212x = - \frac{21}{2}.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 112- \frac{11}{2}
  • Moved a term across without changing its sign → 32- \frac{3}{2}
15

Answer: 383\frac{38}{3}

Cross-multiply to clear both denominators: 2(x+4)=5(x6)2\left(x + 4\right) = 5\left(x - 6\right). Expand, collect the xx terms and divide: x=383x = \frac{38}{3}.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 143\frac{14}{3}
  • Added the fractions instead of cross-multiplying → 227\frac{22}{7}
16

Answer: 72- \frac{7}{2}

m=y2y1x2x1=9(2)3(5)=72m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{-9 - (-2)}{-3 - (-5)} = - \frac{7}{2}.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 27- \frac{2}{7}
  • Subtracted the coordinates in opposite orders → 72\frac{7}{2}
17

Answer: 22-22

Expand the bracket: 5x25=6x35 x - 25 = 6 x - 3. Collect the xx terms on one side and the numbers on the other, then divide: x=22x = -22.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 2-2
  • Moved a term across without changing its sign → 31-31
18

Answer: 17-17

Cross-multiply to clear both denominators: 6(x+4)=3(x9)6\left(x + 4\right) = 3\left(x - 9\right). Expand, collect the xx terms and divide: x=17x = -17.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 11-11
  • Added the fractions instead of cross-multiplying → 13\frac{1}{3}
19

Answer: 23- \frac{2}{3}

m=y2y1x2x1=0(2)2(5)=23m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{0 - (2)}{-2 - (-5)} = - \frac{2}{3}.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 32- \frac{3}{2}
  • Subtracted the coordinates in opposite orders → 23\frac{2}{3}
20

Answer: 21-21

Expand the bracket: 5x25=6x45 x - 25 = 6 x - 4. Collect the xx terms on one side and the numbers on the other, then divide: x=21x = -21.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 1-1
  • Moved a term across without changing its sign → 33-33
21

Answer: 7-7

Cross-multiply to clear both denominators: 2(x5)=3(x1)2\left(x - 5\right) = 3\left(x - 1\right). Expand, collect the xx terms and divide: x=7x = -7.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 9-9
  • Added the fractions instead of cross-multiplying → 135\frac{13}{5}
22

Answer: 2-2

m=y2y1x2x1=7(5)0(1)=2m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{-7 - (-5)}{0 - (-1)} = -2.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 12- \frac{1}{2}
  • Subtracted the coordinates in opposite orders → 22
23

Answer: 46-46

Expand the bracket: 7x+42=6x47 x + 42 = 6 x - 4. Collect the xx terms on one side and the numbers on the other, then divide: x=46x = -46.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 10-10
  • Moved a term across without changing its sign → 34-34
24

Answer: 312- \frac{31}{2}

Cross-multiply to clear both denominators: 6(x+9)=2(x4)6\left(x + 9\right) = 2\left(x - 4\right). Expand, collect the xx terms and divide: x=312x = - \frac{31}{2}.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 292- \frac{29}{2}
  • Added the fractions instead of cross-multiplying → 234- \frac{23}{4}
25

Answer: 8-8

m=y2y1x2x1=6(2)6(5)=8m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{-6 - (2)}{6 - (5)} = -8.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 18- \frac{1}{8}
  • Subtracted the coordinates in opposite orders → 88
26

Answer: 19-19

Expand the bracket: 5x+40=3x+25 x + 40 = 3 x + 2. Collect the xx terms on one side and the numbers on the other, then divide: x=19x = -19.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 3-3
  • Moved a term across without changing its sign → 22-22
27

Answer: 6969

Cross-multiply to clear both denominators: 5(x+9)=6(x4)5\left(x + 9\right) = 6\left(x - 4\right). Expand, collect the xx terms and divide: x=69x = 69.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 4949
  • Added the fractions instead of cross-multiplying → 2111- \frac{21}{11}
28

Answer: 53- \frac{5}{3}

m=y2y1x2x1=7(2)7(4)=53m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{7 - (2)}{-7 - (-4)} = - \frac{5}{3}.

Common mistakes, and the answer each one gives:

  • Inverted the fraction (run over rise) → 35- \frac{3}{5}
  • Subtracted the coordinates in opposite orders → 53\frac{5}{3}
29

Answer: 12- \frac{1}{2}

Expand the bracket: 2x10=6x82 x - 10 = 6 x - 8. Collect the xx terms on one side and the numbers on the other, then divide: x=12x = - \frac{1}{2}.

Common mistakes, and the answer each one gives:

  • Multiplied only the xx by the number outside the bracket → 34\frac{3}{4}
  • Moved a term across without changing its sign → 132- \frac{13}{2}
30

Answer: 15-15

Cross-multiply to clear both denominators: 3(x9)=4(x3)3\left(x - 9\right) = 4\left(x - 3\right). Expand, collect the xx terms and divide: x=15x = -15.

Common mistakes, and the answer each one gives:

  • Multiplied only the numerators by the other denominator → 24-24
  • Added the fractions instead of cross-multiplying → 397\frac{39}{7}