Question

Four times marie's age minus twice lisa's age is -10. lisa is three times as old as marie. how old is marie?

Answer 1

Marie is 5 years old

4m - 2l = -10 ------- x
l = 3m ---------------- y

sub y into x
4m - 2(3m) = -10
4m - 6m = -10
-2m = -10
m = -10/-2
m = 5 years old