Find the surface area of the composite figure

144 cm²

Step-by-step explanation:

This figure is formed by rectangles and triangles, so we need to find the surface area of they and add all to have the surface area of the figure:

area of the rectangles:

4×3 = 12, and there are two of these rectangles

6×3 = 18, and there are just one of that

4×6 = 24, and there are two of these

5×3 = 15, and there are two of these

Now the area of a triangle:

6×4/2 = 12, and there are two of these

12×2 + 18 + 24×2 + 15×2 + 12×2 = 144 cm²

the sum of the lengths of any two sides of a triangle is greater than the length of the third side. if you take the three sides of a triangle and add them in pairs, the sum is greater than (not equal to) the third side. if that is not true, then it is not possible to construct a triangle with the given side lengths.

step-by-step explanation: