X=10

3x+3y = 20

What is the solution (x, y) of the system

First thing first you need to arrange your numbers in away so you can solve and understand.

3 (10) + 3y=20

30+3y=20

-20+3y=20

10=3y

Y=-10/3

Y=-3+1/3

(10, - 10/3)

Step-by-step explanation:

We're told that x = 10. Substitute 10 for x in the 2nd equation:

3 (10) + 3y = 20. Subtracting 30 from both sides, to isolate 3y, we get:

3y = - 10

Dividing both sides by 3, we get: y = - 10/3.

The desired solution is (10, - 10/3).