Answer:
The solution to the system of equations be:
Step-by-step explanation:
Given the system of equations
x + y = 12
-x + 2y = 15
Let us solve the system of equations by elimination
[tex]\begin{bmatrix}x+y=12\\ -x+2y=15\end{bmatrix}[/tex]
adding the equations
[tex]-x+2y=15[/tex]
[tex]+[/tex]
[tex]\underline{x+y=12}[/tex]
[tex]3y=27[/tex]
solve 3y = 27 for y
[tex]3y=27[/tex]
divide both sides by 3
[tex]\frac{3y}{3}=\frac{27}{3}[/tex]
Simplify
[tex]y=9[/tex]
For x+y=12 plug in y = 9
[tex]x+9=12[/tex]
Subtract 9 from both sides
[tex]x+9-9=12-9[/tex]
Simplify
[tex]x=3[/tex]
Therefore, the solution to the system of equations be:
