Lesson 5.85.7 · 5.8 Catch-Up
Start hereWords, worked example, and sentence starters
Learning target I can show I am caught up on Lessons 5.7 · 5.8 by using each lesson's big idea in mixed practice.
Start hereWords for this lesson
Read each word before you begin. Say it out loud.
| Word | What it means | Example |
|---|---|---|
| Surface Area of PrismsSpanish: Área de superficie de prismas | The total area of all bases and lateral faces of a prism. Formula: SA = 2B + lateral area. | SA = 2B + lateral area |
| Surface areaSpanish: Área de superficie | The total area of all the flat sides of a solid. | Paint every outside surface of a box — the total painted area is the surface area |
| Rectangular prismSpanish: Prisma rectangular | A solid box shape with six flat rectangle sides. | A box with 6 flat rectangle sides: top, bottom, front, back, left, right |
| Triangular prismSpanish: Prisma triangular | A solid with two triangle ends and three flat rectangle sides. | Shaped like a tent or a wedge of cheese — 2 triangle ends + 3 rectangle sides |
| FaceSpanish: Cara | One flat side of a solid shape. | A triangular prism has 5 faces: 2 triangles + 3 rectangles |
| NetSpanish: Plantilla (desarrollo plano) | A flat shape that folds up into a solid. | Unfold a triangular prism flat: you see 2 triangles and 3 rectangles side by side |
How it worksWorked examplesurface area of a square pyramid
These numbers are not on your problems. The steps are. Follow them with your own numbers.
A square pyramid has a base 10 cm on each side. Each triangular face has a slant height of 12 cm. Find the surface area.
- The net is a square base with 4 congruent triangles, one on each side.
- Area of the square base. 10 × 10 = 100
- One triangular face uses the slant height. ½ × 10 × 12 = 60
- Four faces plus the base. 60 × 4 = 240, then 240 + 100 = 340
Answer: The surface area is 340 square centimeters (340 cm²).
Now you trySame steps, your turn
The steps are the same as the worked example. The numbers are yours. Do the work.
A square pyramid has a base 14 in. on each side and a slant height of 9 in. Find the surface area.
- Sketch the net. Square: Triangles:
- Area of the square base. × = in²
- One triangular face. ½ × × = in²
- All the faces. × = , then + = in²
Say it and write itSentence starters
Finish each sentence out loud with a partner. Then use them in your writing.
- The base is a with an area of .
- Each triangular face has a base of and a slant height of .
- There are triangular faces, so together they cover .
- The surface area is because I added .
Word bank pyramidbaseslant heightlateral faceapextrianglesquarecongruentaddsurface areasquare unitsnet
Watch outA common mistake
A common mistake in Surface Area of Pyramids is finding the four triangular lateral faces correctly (½ × base edge × slant height, times 4) and then stopping — forgetting to add the base area at the end. This leaves the total surface area too small by exactly the base's area. Before you submit, ask: 'Did I add the base area to the four lateral faces, or did I stop after the sides?'
Lesson 5.85.7 · 5.8 Catch-Up
Catch-UpSkill bridge
Learning target I can show I am caught up on Lessons 5.7 · 5.8 by using each lesson's big idea in mixed practice.
-
1Circle the letter of the best answer. Show how you know.
(Lesson 5.7) What is the surface area of a rectangular prism with l = 5 cm, w = 4 cm, h = 3 cm?
- A47 cm²
- B60 cm²
- C94 cm²
- D94 cm³
Hint You need surface area — the total of all 6 face areas of the 5 × 4 × 3 prism — not the space inside.
FormulaPut the numbers inWork it outAnswer with its unit- 1Name itWhich measure is asked?
- 2Write the formulaBefore any numbers.
- 3SubstituteMatch each letter.
- 4Unitunits, sq units, or cubic?
-
2Circle the letter of the best answer. Show how you know.
(Lesson 5.7) How many faces does a triangular prism have?
- A3
- B4
- C5
- D6
Hint Picture a tent or a triangular chocolate box: two triangle ends plus rectangles wrapping around the sides.
Show your work -
3Circle the letter of the best answer. Show how you know.
(Lesson 5.8) A square pyramid has a base edge of 5 in and a slant height of 7 in. What is the surface area?
- A70 in²
- B95 in²
- C95 in³
- D120 in²
Hint A square pyramid has TWO kinds of faces: one square base (5 × 5) and four identical triangles with slant height 7.
FormulaPut the numbers inWork it outAnswer with its unit- 1Name itWhich measure is asked?
- 2Write the formulaBefore any numbers.
- 3SubstituteMatch each letter.
- 4Unitunits, sq units, or cubic?
-
4Circle the letter of the best answer. Show how you know.
(Lesson 5.8) How many lateral (triangular) faces does a square pyramid have?
- A3
- B4
- C5
- D6
Hint Lateral faces are the slanted triangles on the sides — the square base itself doesn't count.
Show your work
Explain your thinkingDisplay B has the largest surface area (280 in²). What contributes more to the total — the base or the lateral faces? Why?
Sentence starter For Display B, the base area is ___ in² and the total lateral area is 4 × ___ = ___ in². The ___ contribute(s) more because ___.