Question

How do you solve, 2=2y-x and 23=5y- 4x , using the substitution method

Answer 1

2= 2y - x
23 = 5y - 4x

isolate the x in the first equation

x = 2y - 2

now use this to substitute x in the second equation

23 = 5y - 4 (2y - 2)
23 = 5y - 8y + 6
23 = -3y + 6
-3y = 17
y = -5 2/3 (5.6 repeating )

now use that to find x in either equation.

2 = 2 (-5.66666) - x
2= -11.3 repeating - x
13.3 repeating = -x
x = -13.3 repeating

optional ** use the second equation to check