What is the surface area of the figure below? A. 120 m²
B. 126 m²
C. 140 m²
D. 156 m²

120m^2

Step-by-step explanation:

Let's start with the bottom. Since the height, base and width are all 4m, we can say that one square = 16 m^2.

There are 5 squares (counting the bottom), and 16 * 5 = 80.

Now the top triangles. We can split the bigger triangle in half. The base is 4m, you can tell from the bottom. To find the area of the triangle, split 4 in half to find the base of the smaller triangles, which equals 2.

Now for the smaller triangles, the base is 2 and the height is 5. We know that to find a triangle's area, you do (b * h)/2, which is (2*5)/2 = 5.

The big triangle is 2 of the small triangles, so you can multiply the smaller triangle's area by 2, which is 5 * 2 = 10.

There are 4 identical triangles at the top-- so 10 * 4 = 40.

80 + 40 = 120.

Hope this helps!

your answer would be 10x - 1