Answer:
y = 3
x = -15
Explanation:
When substituting, we want to get rid of one of the variables. (It's easiest ot find the variable in terms of other variable)
so, we know that...
x + 5y = 0
- 5y - 5y
x = -5y
We can plug this x-value into the second equation to find our y-value:
3y + 2x = -21
3y + 2(-5y) = -21
3y - 10y = -21
-7y = -21
÷ -7 ÷ -7
y = 3
So, if x = -5y,
x = -5y
x = -5(3)
x = -15
(we can test these values in one of the original equations):
x + 5y = 0
(-15) + 5(3)= 0
-15 + 15 = 0
{true}
so, y = 3 ; and x = -15
hope this helps!! :)