Question

How do you solve the following linear system: #-2x+y=1 , y= -5x-4 #?

Answer 1

`x=-5/7,y=-3/7`

Explanation:

First of all, we're going to make the `x` switch size in the 2nd equation.

`y = -5x - 4 iff y + 5x = -4`

Now we substract the 1st line to the 2nd one and the system solves itself pretty quickly.

`-2x + y = 1,y+5x = 4 iff -2x + y = 1, 7x = -5 iff -2x + y = 1,x=-5/7 iff x=-5/7,y=1 - 10/7 iff x=-5/7,y=-3/7`