Answer: A=490
Step-by-step explanation:
Formula - A = 2 ( wl + hl + hw)
2(7•14+7•14+7•7) = 490
let 1/u=x and 1/v=y
so,
-3x-8y=20
-5x+y=19
then solve for it
When you find A and B, back-substitute for A and B and continue from there.
A.
3x – 8
B.x/3-8
C.x-8/3
D.8-x/3