Answer:
4 inches by 2.5 inches
Step-by-step explanation:
X = -6y - 12
4x + 5y =-39
4x + 5y = -39
-4(-6y - 12) + 5y = -39
-4(-6y) + 4(12) + 5y = -39
24y + 48 + 5y = -39
29y + 48 = -39
29y = -87
y = -3
x = -6y - 12
x = -6(-3) - 12
x = 28 - 12
x = 6
(x, y) = (6, -3)
Answer: 70
Step-by-step explanation:
12*10 = 120-50 = 70
We need to FOIL that out and then get it into standard form to see what our A, B, and C are. FOILing gives us

. If we move the 7 over by subtraction and set it equal to 0, we have

. In order to avoid a negative leading coefficient, we can change all the signs to get

so A = 1, B = 0, C = -18, first choice above.