What is the area of the shaded part of the figure?

a.
144 mm²

b.
288 mm²

c.
432 mm²

d.
720 mm²

The answer is A. 144. I came up with this by finding the area of the unshaded figure. That area is 144. Then, I came up with the area of the triangle. That's is 288. Finally, I subtracted the area of the triangle from the area of the square. 288-144=144.

Basic algebra equation. first set up your equation: divide out 9.and now you are left with 2x + 4 = 8.