Finding a perpendicular gradient Revision Card

AI generatedAlgebraGCSE Higher

Use the negative reciprocal for non-zero finite gradients.

For a non-vertical straight line, use .
The gradient is change in divided by change in . The intercept is the value when .
Substitute a known point to find missing constant. Show the same operation on both sides.

Example 1

Find the gradient of a line perpendicular to this line.

Read the coefficient of

Take the negative reciprocal. The two gradients multiply to −1.

Find the gradient of a line perpendicular to this line.

Read the coefficient of

Take the negative reciprocal. The two gradients multiply to −1.

Question 1

Find the gradient of a line perpendicular to this line.

Check answer

Read the coefficient of

Take the negative reciprocal. The two gradients multiply to −1.

Question 2

Find the gradient of a line perpendicular to this line.

Check answer

Read the coefficient of

Take the negative reciprocal. The two gradients multiply to −1.

Question 3

Find the gradient of a line perpendicular to this line.

Check answer

Read the coefficient of

Take the negative reciprocal. The two gradients multiply to −1.

Question 4

Find the gradient of a line perpendicular to this line.

Check answer

Read the coefficient of

Take the negative reciprocal. The two gradients multiply to −1.

Question 5

Find the gradient of a line perpendicular to this line.

Check answer

Read the coefficient of

Take the negative reciprocal. The two gradients multiply to −1.