Question

Solve the system of equations using substitution.
for a medal
y = 3x + 1
y = 4x

Answer 1

y = 4x
so sub 4x in for y in the other equation

y = 3x + 1
4x = 3x + 1 -- subtract 3x from both sides
4x - 3x = 1 -- combine like terms
x = 1

now sub 1 in for x in either equation to find y
y = 4x
y = 4(1)
y = 4

now we can check our answers...
y = 3x + 1
4 = 3(1) + 1
4 = 3 + 1
4 = 4 (correct)

so x = 1 and y = 4 or (1,4)
any questions ?