Question

Find the solution of this system of equations.

Separate the x- and y-values with a comma.
x = 10 + y
-3x + y = -28

Answer 1

We know that:

x = 10 + y

In the next equation {-3x + y = -28} x is the same as the first, so:

-3(10 + y) + y = -28

-30 - 3y + y = -28

-30 - 2y = -28

We add 30 to both sides:

-2y = 2

and divide both sides by (-2):

y = -1

Now we can put y = -1 to the first equation:

x = 10 + y

x = 10 - 1

x = 9

So,

the solution of this system of equations is:

(9, -1)