Coordinate geometry in the (x,y) plane

Question 1

In the graph of y=mx+c, what does m represent?

Answer 1

The gradient

Question 2

In the graph of y=mx+c, what does c represent?

Answer 2

The y intercept

Question 3

For two points with coordinates (x₁,y₁) and (x₂,y₂), how the gradient of the connecting line be calculated?

Answer 3

(y₂-y₁)/(x₂-x₁)

Question 4

For a line with a gradient m that passes through a point with coordinates (x₁,y₁), how can the equation of the line be calculated?

Answer 4

y=m(x-x₁)+y₁

Question 5

For two points with coordinates (x₁,y₁) and (x₂,y₂), how can the equation of the straight line passing through both points be calculated?

Answer 5

(y-y₁)/(y₂-y₁)=(x-x₁)/(x₂-x₁)

Question 6

For a line with gradient m, what is the gradient of a line perpendicular to it?

Answer 6

-1/m