GCSE Secondary Maths Age 13-17 - Graphs: Perpendicular Lines - Explained

The video tutorial explains how to determine if a line is perpendicular to another by analyzing their gradients. It begins with an introduction to coordinates and perpendicular lines, followed by a detailed explanation of the relationship between perpendicular lines and their gradients. The tutorial then demonstrates how to calculate the gradient of a line passing through two points and how to find the gradient of a line perpendicular to it. Finally, it analyzes a given line equation to determine if it is perpendicular to the original line, concluding with a discussion on mark allocation for the problem.

What is the relationship between the gradients of two perpendicular lines?

• Their gradients are both positive.

• The product of their gradients is zero.

• Their gradients are equal.

• The product of their gradients is -1.

How do you calculate the gradient of a line passing through two points?

• By adding the x-coordinates and y-coordinates.

• By subtracting the x-coordinates from the y-coordinates.

• By dividing the difference in y-coordinates by the difference in x-coordinates.

• By multiplying the x-coordinates and y-coordinates.

What is the gradient of a line perpendicular to a line with gradient -4/3?

• 3/4

• -3/4

• 4/3

• -4/3

How can you find the gradient of the line given by the equation 2y = 3x - 4?

• By rearranging it to y = mx + c form.

• By calculating the midpoint.

• By finding the x-intercept.

• By finding the y-intercept.

What is the gradient of the line with the equation 2y = 3x - 4?

• -2/3

• -3/2

• 2/3

• 3/2

Why is the line with equation 2y = 3x - 4 not perpendicular to line L?

• Because their gradients are both positive.

• Because their gradients are equal.

• Because their gradients are both negative.

• Because their gradients are different.

How many marks are allocated for finding the gradient of the line 2y = 3x - 4?

• One mark

• Two marks

• Three marks

• Four marks