The equation is:
3X - 8Y = 20
-5X - Y = 19
Solution:
-5x - y = 19
-y = 19 + 5x -- (-y = 19 + 5x) -1
y = 19 - 5x
Finding X using Y
3x - 8y = 20
3x - 8(19-5x) = 20
3x - 152 + 40x = 20
43x - 152 = 20
43x = 20 + 152
43x = 172 (divide both sides by 43)
x = 4
Finding Y using X
Y= 19 - 5x
= 19 - 5(4)
= 19 - 20
Y = -1
Checking:
3(4) - 8(-1) = 20
12 + 8 = 20
20 = 20
-5(4) - (-1) = 19
-20 + 1 = 19
19 = 19
