Question

Find the equation of the line that passes through (3,-4) and is parallel to 3x+y+2=0

Leave your answer in the form y=mx+c

Answer 1

Since it’s parallel to 3x+y+2=0 then it must be of the form 3x+y+k=0. Since (3,-4) is on the line we have 0=3*3-4+k=k+5, therefore k=-5 and the equation is 3x+y-5=0

In the form y=mx+c this becomes y=-3x+5

Answer 2

y=-3x+5

Explanation:

it parallel to 3x+y+2=0 => line is: 3x+y+c=0

It through (3;-4) => 3(3)+(-4)+c=0 <=> c=-5

Line is 3x+y-5=0 => y=-3x+5