Question

Find the equation of the line containing the point

P(1, 2)
and parallel to the graph of
5x + y = −2.

Answer 1

y = -5x + 7

Explanation:

Parallel lines on a graph have the same slopes/gradients.

m1=m2

First you want to rewrite the equation of the graph given. So put the 5x to the other side and you will have:

y = -5x -2

This means that the equation that we need must have the gradient -5 (bc it is m in y=mx+c)

The equation will be y = -5x + c

However we must still find c aka the y intercept.

Sub the point we are given (1,2) into the equation

We will have:

2 = -5(1) + c

2 = -5 + c

7 = c

Now that we know c, we know what the equation of the line is. Just sub it in (without 1 and 2)

y = -5x + 7