Question

Solve for x and y for the system: 4x - 6y = -20 3x + 6y = 48 What is x + y?

Answer 1

We'll do this by substitution (Gaussian Elimination isn't worth it for 2 equations).

Answer 2

4x-6y=-20
3x+6y=48
--------- +
7x=28
x=4

3.4+6y=48
12+6y=48
6y=36
y=6

x+y=10

Answer 3

\[\begin{align}
4x=6y-20\\
x=\tfrac{3}{2}y-5\\
\tfrac{9}{2}y-15+6y=48\\
21y=126\\
y=6\\
x=9-5=4\\
x+y=10
\end{align}\]

Answer 4

Thank you so very much- I had 6.. :(