Final answer:
To find the surface area of the composite figure, calculate the area of each individual shape (rectangle and triangle) and then add them up.
Step-by-step explanation:
To find the surface area of a composite figure, we need to calculate the area of each individual shape and then add them up. Let's break down the figure into two parts: a rectangle and a triangle.
The rectangle:
The length of the rectangle is 4 cm and the width is 5 cm, so the area is 4 cm * 5 cm = 20 cm².
The triangle:
One of the triangle's sides is the same as the rectangle's width, which is 5 cm. The base of the triangle is 3 cm. So, the area of the triangle is (1/2) * base * height = (1/2) * 3 cm * 5 cm = 7.5 cm².
Now, we can find the total surface area by adding the areas of the rectangle and the triangle: 20 cm² + 7.5 cm² = 27.5 cm².