Answer:
(2u+8)(2u+10) inches^2=4u^2+36u+80 inches^2
Explanation:
I don't know what the options are. But I'll try to help you anyway. Is that variable for the width of the frame... u? We'll just use u.
So the area of a rectangle is found using length* width. To find the combined area of the mat and the photo, we need the combined length and the combined width.
combined length=u+8+u
(Think of it from the top to the bottom: the top strip has a length of u inches, 8 is given, and the bottom strip is also u inches long.) You can simplify it to get 2u+8 inches.
combined width=u+10+u=2u+10 inches
To find the area, you need to multiply these dimensions.
(2u+8)(2u+10) inches^2
I think this would be your answer for Part B, because it's factored.
I think for Part A, you need to multiply it all out.
=2u(2u+10) + 8(2u+10)
=4u^2+20u + 16u+80
=4u^2+36u+80 inches^2
Hope I could help you!