calculating the gradient of a line graph

1. Gradient. y = mx + c
 The equation of a straight line y = mx + c has a gradient of
m and its intercept on the y axis is (0,c).
 Lines with the same gradient (m) are parallel.
Example 1:
Write down: (a) the gradient and (b) the intercept on the y axis of the
line y = 7x – 3.
(a) gradient = 7.
(b) intercept on the y axis is (0,-3).
Example 2:
Write down: (a) the gradient and (b) the intercept on the y axis of the
line 2x – 3y = 18.
Here the equation must be rearranged in the form y = mx + c
3y = 2x – 18
y = 2
/3x – 6.
(a) gradient = 2
/3.
(b) intercept on the y axis is (0,-6).
Questions.
For each of the following questions write down:
(a) the gradient,
(b) the intercept on the y axis.
1. y = -2x + 5. 5. y = -4x – 3.
2. y = 5x + 4 6. y = 8 + 9x
3. y = 2x – 7. 7. y = 7 – 2x.
4. y = ¼ x + 9. 8. y = 2 – 3x.
For each of these questions find the same as above, but they will need
rearranging first.
9. 2x + y = 3. 12. x + 3y = 6.
10. 3x – y = 5. 13. 3x – 5y = 10.
11. x – 2y = 8. 14. 3x + 4y – 12 = 0.
15. The gradient of the line is 6 and its intercept on the y axis is (0,7).
Write the equation of the line.