Year 9 Gradient and Linear Equations Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 linear relationships & graphs worksheet.
Year 9 Gradient and Linear Equations Worksheet — Level 3 — Practice Set 3 — Answers
Show your working. Gradient = rise ÷ run; the equation of a line can be written as y = (gradient)x + (y-intercept).
Answer: y = −5x
- y = −5x + (y-intercept)
- −15 = −5 × 3 + (y-intercept)
- y-intercept = −15 − (−15) = 0
- y = −5x
Answer: gradient 4; y-intercept 2
In y = (gradient)x + (y-intercept), the number multiplying x is the gradient and the constant is where the line crosses the y-axis.
- AYes
- BNo
Answer: No
Substitute x = 2: y = 1 × 2 − 8 = −6, not −9.
Answer: gradient 6; y-intercept 4
In y = (gradient)x + (y-intercept), the number multiplying x is the gradient and the constant is where the line crosses the y-axis.
- AYes
- BNo
Answer: No
Substitute x = 5: y = 1 × 5 + 3 = 8, not 6.
Answer: gradient 1; y-intercept −3
In y = (gradient)x + (y-intercept), the number multiplying x is the gradient and the constant is where the line crosses the y-axis.
- AYes
- BNo
Answer: No
Substitute x = 0: y = −4 × 0 − 4 = −4, not −1.
- AYes
- BNo
Answer: No
Substitute x = 4: y = −1 × 4 + 7 = 3, not 2.
- AYes
- BNo
Answer: Yes
Substitute x = 4: y = 1 × 4 − 9 = −5, which matches.
Answer: gradient −2; y-intercept −7
In y = (gradient)x + (y-intercept), the number multiplying x is the gradient and the constant is where the line crosses the y-axis.
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.