Answer:
mom mom mom mom mom mom b mom
-7
Step-by-step explanation:
Because there is no multiplication, it is just the x^2 terms. There is a -(-2x^2) and a -9x^2, so it is 2x^2 and -9x^2 or -7x^2, so the coefficient is -7.
Equation
A = (b1 + b2)*h /2
Givens
b1 = 5 feet
b2 = 7 feet
h = 3 feet
Sub and solve
Area = (5 + 7)*3/2
Area = 12*3/2
Area = 36/2
Area = 18 Square feet.