Question

Solve the system of equations. Show work Please
-2x – 1 = y
x = -y + 3

Answer 1

multiply bottom times 2, then add both equations together. you will be left with only y, isolate y. then repeat process from the beginning for x

Answer 2

\[\large -2x – 1 = y[1]\]
\[\large x = -y + 3 [2]\]
The first equation tells you that "y" can be written as -2x-1.
So you rewrite y in the second equation as -2x-1.
\[\large x=-(-2x-1)+3\]
That's your y in the brackets.
Expand it out or in other words, distribute.
\[\large x=--2x--1+3\]
Two minus signs make a plus sign.
\[\large x=+2x+1+3\]
Don't need the plus sing in the very front because it doesn't look good.
\[\large x=2x+1+3\]
Gather like terms.
\[\large x=2x+4\]
\[\large x+4=0\]
Move the 4 to the other side. Remember to change the sign of a term when it moves to the other side of the equal sign.
\[\large x=-4\]
TO find y, just easily put the x-value into the first equation.
\[\large y=-2x-1\]
\[\large y=-2(-4)-1\]
\[\large y=8-1\]
\[\large y=7\]