432 x 0.1 = 43.2
432-43.2= 388.8
Mark up
388.8 + 72 = 460.8
Answer C : 3x^2+7xy-2y^2
equivalent to the following expression


Combine like terms

2x^2 + x^2 is 3x^2
4xy+3xy is 7xy
-y^2-y^2 is -2y^2
So expression becomes

Answer C is correct
Multiply 20 by the numerator and then divide by the denominator:
20 * 3 = 60
60 / 4 = 15
20 * 3/4 = 15