Kind of lost, can anyone please help me find the answer and explain? Id really appreciate it.

B. 45

Step-by-step explanation:

do 12×12 which is 144 then Davide it by 2 because it's a triangle then do 9×3 which is 27 then subtract that from 72 and you get 45.

45

Step-by-step explanation:

what is the area of a triangle (At) ?

At = base line × height / 2 = 12×12/2 = 72 in²

what is the area of a rectangle (Ar) ?

Ar = length × width (or height - however you see or name the second dimension)

so, the area of that inner rectangle is 3×9 = 27 in²

now the main question is about the area of the triangle without the inner rectangle.

this is simply At - Ar = 72 - 27 = 45 in²

that's it. you only need to translate the English sentence into the corresponding mathematical expressions and use the mathematical operators just as the sentence states.

we did exactly and nothing else than what the original problem statement said.

5/12, or 5: 12

step-by-step explanation: