The equation would look like this:
3y - (y×13) = 10
To solve this, we need to be able to get y by itself.
First, put together the 13 and y in the parentheses.
3y - (y×13) = 10
3y - 13y = 10
Next, subtract the 13y from the 3y
3y - 13y = 10
-10y = 10
Finally, divide by -10 to find what y is equal to.
-10y = 10
-10y ÷ -10 = 10 ÷ -10
y = -1
The number you are looking for is -1
