-2
5y+8=7y 2y=8 y=4
Presumably this is a simultaneous equation question in the form of: 4x-y = 32 4x+5y = -16 Subtract the bottom equation from the top equation remembering that a -- is equal to a + so 32--16 is +40 and that -+5y-y is -6y: -6y = 48 Divide both sides by -6 to find the value of y: y = -8 Substitute the value of y into the original equations to find the value of x: So: x = 6 and y = -8
(9,3)
5y+8=7y subtract 5y from each side , 5y+8=7y -5y -5y 8=2y /2 /2 4=y
2y+5y=10 7y=10 y=10/7
y = -6
(-5, 2)
The Commutative Property of Addition.
x=(-5y-1)/3
If: 4x = 5y Then: x = 5y/4
5y + 7 = 25y = -5y = -1