Answer:
b^2 + 2b <= 168
Explanation:
The base is b.
The height, h, is 4 in. greater than twice the base, so the height is 2b + 4.
The area of a triangle is bh/2. We replace h with the expression for height.
A = bh/2 = b(2b + 4)/2 = (2b^2 + 4b)/2 = b^2 + 2b
The area is b^2 + 2b.
The area is no more than 168 in.^2, so it is less than equal to 168 in.^2.
b^2 + 2b <= 168
("<=" means "less than or equal to")
Since you don't show the choices, choose an inequality that is equivalent to the one just above.