Answer:
y = -1
(and x = 3)
Explanation:
5x + 3y = 12
4x - 5y = 17
First, we'll solve for x in terms of y
5x = 12 - 3y
x = 12/5 - 3/5y
x = 2.4 - 0.6y
Then substitute that mess into the next equation:
4(2.4 - 0.6y) - 5y = 17
and solve for a numerical value of y
9.6 - 2.4y - 5y = 17
-7.4y = 7.4
y = -1
To finish and check, we can use that to solve for x:
x = 2.4 - 0.6(-1)
x = 2.4 + 0.6
x = 3
And check both values in the original equations.
5x + 3y = 12
4x - 5y = 17
5(3) + 3(-1) = 15 - 3 = 12
4(3) - 5(-1) = 12 +5 = 17
LMK if you have questions.