Problem: how do you solve this algebra equation y=8/7 5x-4(8/7)=-1
y=8/7
5x-4(8/7)=-1
5x - 4(8/7) = -1
5x - 32/7 = -1
5x - 32/7 + 32/7 = -1 + 32/7
5x = -7/7 + 32/7
5x = 25/7
5x / 5 = (25/7) / 5
x = 5/7
The first equation serves no purpose unless you want to
substitute it into the second equation, giving 5x - 4y = -1.
That won't take you anywhere.