Tuesday, February 21st • Please complete warm up and write down the

Homework

WARM UP1. Solve the Proportion

2. Find the Surface Area

12

23 9

x

4 in.3 in.5 in.

Joke of the Day What candy is never on

time?

Choco-late

Weekly Review Answers

Interims are only 2 weeks away!!!!!!!!!!

Goal for today

Volume and Surface Area Triangular

AND Rectangular

PRISMS

Surface Area

How would you describe:

Net

Volume

And

Surface Area

Part 1: Surface Area

1. Using a Net

2. Using a Formula

Find the area to each shape in the net. Add the areas up to find the TOTAL AREA

Draw a net to help you see each face of the prism.

Use the formula A = lw to find the area of each face.

Nets

Finding the Areas of each!

A: A = 5 2 = 10

B: A = 12 5 = 60

C: A = 12 2 = 24

D: A = 12 5 = 60

E: A = 12 2 = 24

F: A = 5 2 = 10

S = 10 + 60 + 24 + 60 + 24 + 10 = 188Add the areas of each face.

The surface area is 188 in2.

You Try #1Rectangle

Remember!

Area of a TRIANGLE is

½ x b x h

You Try #2Triangular Prism

12 in

5 in

4 in

You Try #3Triangular Prism

11 in

7 in3 in

Surface Area with Formulas

#1 Try Together!

SA= 2(lw)+2(wh)+2(lh) SA=_____________+_____________+___________ SA=_____________+_____________+___________ SA=_________ 

#2 You Try!

SA= 2(lw)+2(wh)+2(lh) SA=_____________+_____________+___________ SA=_____________+_____________+___________ SA=_________ 

Part 2: Volume

• To find the volume of any prism, you can use the formula V= Bh,where B is the area of the base, and h is the prism’s height.

• The base of a RECTANGULAR prism is a rectangle so the base is: l x w

• To find the volume of a triangular prism, B is the area of the triangular base so the base is:

• ½ x b x h

V = lwh Write the formula.

V = 29 • 12 • 16 l = 29; w = 12; h = 16

Multiply.V = 5,568 in3

16 in.

29 in.

12 in.

#1 You Try!A=bh

B= l x w

A rectangular prism with base length 6 ft, width

5 ft, and height 7 ft

#2 You Try!A=bh

B= l x w

V = Bh Write the formula.

V = ( • 3.9 • 1.3) • 412__ B = • 3.9 • 1.3; h = 4.1

2__

Multiply.V = 10.14 m3

#3 Try Together!A=bh

B= ½ x b x h

The bases of a prism are always two congruent, parallel polygons.

Caution!

V = Bh Write the formula.

V = ( • 6.5 • 7) • 612__ B = • 6.5 • 7; h = 6.1

2__

Multiply.V = 136.5 ft 3

#4 You TryA=bh

B= ½ x b x h

V = Bh Write the formula.

V = ( • 4.5 • 9) • 512__ B = • 4.5 • 9; h = 5.1

2__

Multiply.V = 101.25 ft3

4.5 ft5 ft

9 ft

#5 You TryA=bh

B= ½ x b x h