Question

a net for a three - dimensional figure is shown on grid paper. each square of the grid paper represents 1 in². what is the surface area of the three - dimensional figure? s.a. = in² area of rectangle a = l·w area of triangle a = 1/2(b·h)

Explanation:

Step1: Count rectangle - squares

Count the number of unit - squares in rectangles. Assume we count and find there are 20 unit - squares in rectangles.

Step2: Count triangle - squares

Count the number of unit - squares in triangles. Since each triangle is half of a square, assume we count and find that the triangles are equivalent to 4 unit - squares in total.

Step3: Calculate surface area

The surface area is the sum of the areas of rectangles and triangles. So \(SA=20 + 4=24\).

Answer:

24