We have two right triangles and three different rectangles.
The formula of an area of a right triangle:

l₁, l₂ - legs
We have l₁ = 20cm and l₂ = 21cm. Substitute:

The formula of an area of a rectangle:

l - length
w - width
We have:
rectangle #1: l = 22cm, w = 29cm

rectangle #2: l = 22cm, w = 21cm

rectangle #3: l = 22cm, w = 20cm

The total Surface Area of the triangular prism:

Answer:
Just a guess but I think 5
Step-by-step explanation:
The top right square on all boxes is the difference of the second box and the first box which equals the third box. This rule is applied to all of the other boxes so if I'm not wrong the question mark should be 5
The answer to your question is 8.6
Answer:
Step-by-step explanation:
2x * 2x = 4x^2 and -11 * 11 = -121