Let : T = Theresa age H = her brother We know : T = H - 14 T + H = 35 Substitute T H -14 + H = 35 2H - 14 = 35 2H = 49 H = 49/2 = 24.5 Since we know H = 24.5 we then can substitute it to either equation. T = H - 14 T = 24.5 - 14 T = 10.5 Theresa is 10.5 years old Her brother is 24.5 years old
