Question

Give the equation of the line passing through the point (3,−21) that is parallel to
y= −5x+9.

Answer 1

y=-5x-6 this is because you take m from the equation and use the points in y-y1=m(x-x1)

Answer 2

y=-5x-6

Explanation:

Parallel means you are looking for an equation that has the same slope as the one given.

The slope of y=-5x+9 is -5.

All I did was compare it to y=mx+b where m is slope and b is y-intercept.

So our equation is in the form y=-5x+b.

We want to find b such that y=-5x+b goes through (3,-21).

So we can plug in our point that is on this line so that that happens.

-21=-5(3)+b

-21=-15+b

Add 15 on both sides

-6=b

b=-6

So the line that is parallel to y=-5x+9 while going through (3,-21) is y=-5x-6.