Circle plus triangle = 43 circle plus square = 37 triangle + square = 40 circle plus square

Circle plus triangle = 43 circle plus square = 37 triangle + square = 40 circle plus square

Circle plus triangle = 43 circle plus square = 37 triangle + square = 40
Add the three and you'll get
Circle + triangle + square = (43 + 37 + 40) △ 2 = 120 △ 2 = 60
therefore
Circle = 60-40 = 20
Triangle = 60-37 = 23
Square = 60-43 = 17