Digits, Grade 7, Volume 1, Homework Helper

### 5-4: TEKS Practice

• 1. Find the surface area of the square pyramid. • 2. Error Analysis A student incorrectly says the surface area of the square pyramid is 1,764 cm2. • a. What is the correct surface area?

• b. Which statement best describes an error the student likely made?

• A. The student used the height of the pyramid, 40 cm, rather than the slant height of the pyramid, 41 cm, to find the lateral area.

• B. The student used the side length of the base of the pyramid, 18 cm, rather than the height of the pyramid, 40 cm, to find the lateral area.

• C. The student used the height of the pyramid, 40 cm, rather than the side length of the base of the pyramid, 18 cm, to find the lateral area.

• D. The student used the slant height of the pyramid, 41 cm, rather than the height of the pyramid, 40 cm, to find the lateral area.

• 3. Open-Ended Think of an object that has the shape of a square pyramid. It could be pointed up, down, or to the left or right.

• a. Sketch a square pyramid that has the shape of the object.

• b. What information could you use to find the surface area of a square pyramid? Select all that apply.

• A. the side length of the base

• B. the lateral area

• C. the slant height of the pyramid

• D. the area of the base

• E. the perimeter of the base

• F. the height of the pyramid

• 4. Think About the Process You want to find the surface area of the square pyramid. You use the formula S.A. = L.A. + B, where L.A. represents the lateral area of the pyramid and B represents the area of the base. • a. Which equations do you use for L.A. and B?

• A. cap l .cap a . equals , 1 half , open , 12 squared , close open 9 close semicolon b equals , 9 squared

• B. cap l .cap a . equals , 1 half , open 4 middle dot 9 close open 12 close semicolon b equals , 9 squared

• C. L.A. = (4 · 12)(9); B = 122

• D. cap l .cap a . equals , 1 half , open 4 middle dot 12 close open 9 close semicolon b equals , 12 squared

• b. What is the surface area of the square pyramid?

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