Question

Use substitution to solve the system of equations.
y + 1 = x
-2x + 3y = 2


a) (5, 4)
b) (-6, 3/2)
c) (1/2, 15)
d) (1/4, 1)

Answer 1

your first equation is x=1+y

what we can do is now 'substitute' 1+y instead of the x in the second equation.
-2(1+y)+3y=2
expand the bracket
-2-2y+3y=2
add two to both sides
-2y+3y=4
y=4

we know now y=4
the first equation x=1+y
so x=1+4
x=5

(5,4)