Question

What is an equation of the line that passes through the point (−2,−3) and is parallel to the line 4x-y=1?

Answer 1

y= 4x +5

Explanation:

Let's rewrite the equation so that it is in the form of y=mx+c, where m is the gradient and c is the y-intercept.

4x-y=1

y= 4x -1

parallel lines have the same gradients. Thus the gradient of the line is 4.

y=4x+c

To find c, substitute a pair of coordinate.

When x=-2, y= -3,

-3= 4(-2) +c

-3= -8 +c

c= 8 -3

c= 5

Thus, the equation of the line is y= 4x +5.