Question

Solve 2x + y = 7
x – y = –4

Answer 1

y=5
x=1

Answer 2

We have
\[2x+y=7\]
and
\[x-y=-4\]
We'll use substitution method here, Find x in terms of y from second equation, we have
\[x-y=-4\]
Add y to both the sides
\[x=y-4\]
Let's substitute this in first equation
\[2(y-4)+y=7\]
\[2y-8+y=7\]
add 8 to both the sides
\[3y=15\]
divide both sides by 3, we get
\[y=5\]
now sunstitute this in the value of x we found earlier
\[x=y-4\]
\[x=5-4\]
we get
\[x=1\]
So x=1 and y=5