Year 9 Gradient and Linear Equations Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 9 linear relationships & graphs worksheet.
Year 9 Gradient and Linear Equations Worksheet — Level 3 — Answers
Show your working. Gradient = rise ÷ run; the equation of a line can be written as y = (gradient)x + (y-intercept).
1.Does the point (−2, −12) lie on the line y = 2x − 8?
- AYes
- BNo
Answer: Yes
Substitute x = −2: y = 2 × (−2) − 8 = −12, which matches.
2.For the line y = −6x − 1, write the gradient and the y-intercept.
Answer: gradient −6; y-intercept −1
In y = (gradient)x + (y-intercept), the number multiplying x is the gradient and the constant is where the line crosses the y-axis.
3.A line has a gradient of 5 and passes through (3, 18). Find its equation.
Answer: y = 5x + 3
- y = 5x + (y-intercept)
- 18 = 5 × 3 + (y-intercept)
- y-intercept = 18 − 15 = 3
- y = 5x + 3
4.A line has a gradient of 4 and passes through (1, 12). Find its equation.
Answer: y = 4x + 8
- y = 4x + (y-intercept)
- 12 = 4 × 1 + (y-intercept)
- y-intercept = 12 − 4 = 8
- y = 4x + 8
5.A line has a gradient of −1 and passes through (2, −3). Find its equation.
Answer: y = −x − 1
- y = −1x + (y-intercept)
- −3 = −1 × 2 + (y-intercept)
- y-intercept = −3 − (−2) = −1
- y = −x − 1
6.A line has a gradient of −1 and passes through (−4, 13). Find its equation.
Answer: y = −x + 9
- y = −1x + (y-intercept)
- 13 = −1 × (−4) + (y-intercept)
- y-intercept = 13 − 4 = 9
- y = −x + 9
7.A line has a gradient of −5 and passes through (4, −26). Find its equation.
Answer: y = −5x − 6
- y = −5x + (y-intercept)
- −26 = −5 × 4 + (y-intercept)
- y-intercept = −26 − (−20) = −6
- y = −5x − 6
8.For the line y = x + 9, write the gradient and the y-intercept.
Answer: gradient 1; y-intercept 9
In y = (gradient)x + (y-intercept), the number multiplying x is the gradient and the constant is where the line crosses the y-axis.
9.A line has a gradient of 5 and passes through (−3, −21). Find its equation.
Answer: y = 5x − 6
- y = 5x + (y-intercept)
- −21 = 5 × (−3) + (y-intercept)
- y-intercept = −21 − (−15) = −6
- y = 5x − 6
10.A line has a gradient of 4 and passes through (3, 12). Find its equation.
Answer: y = 4x
- y = 4x + (y-intercept)
- 12 = 4 × 3 + (y-intercept)
- y-intercept = 12 − 12 = 0
- y = 4x
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.