Substitution & Formulas Lesson

Substitution & Formulas Lesson

​Plug and Chug

Multiple Choice

If y=6, evaluate 4y

• 2

• 46

• 24

• 10

Multiple Select

Choose ALL that are correct.

Which expression has x=2 as its solution?

• 2x=22

• 5x=10

• 3x=6

• 7x=72

​A formula is a math rule (an equation)

​

​When given a formula, you PLUG & CHUG

​

​A cube is a 3-dimensional prism with all side lengths the same:

​Surface Area is the area of ALL faces.

​How many faces does a cube have?

​How many faces does a cube have?

​A cube has 6 faces

​Why do you think we multiply by 6?

​To find the surface area of this cube:

6 x 3²​

​To find the surface area of this cube:

6 x 3²

6 x 3 x 3​ = 54 sq units

Multiple Choice

If the side of a cube is 4 in, find its Surface Area. (SA= 6s²)

exponents first!

• 16 sq in

• 48 sq in

• 96 sq in

• 4096 sq in

Multiple Choice

If s=5, evaluate SA= $$6s^2$$  

Exponent first, then multiply!

• 22

• 121

• 150

• 900

Multiple Choice

If s=2, evaluate $$6s^2$$  

• 10

• 144

• 24

• 116

​Plug & Chug

​Remember: Multiplication is Commutative:

It doesn't matter what order you multiply.​

Multiple Choice

Find the volume of a prism with length of 5 inches, width of 2 inches, and a height of 4 inches. (V = l · w · h)

• 40 cubic inches

• 11 cubic inches

• 54cubic inches

Multiple Choice

Find the volume of a prism with length of 10 inches, width of 2.5 inches, and a height of 7 inches. (V = l · w · h)

• 175 cubic inches

• 250 cubic inches

• 19.5 cubic inches

​Remember, all the side lengths are the same.

Its the same thing as side x side x side​

Multiple Choice

The side of a cube is 3". Find the volume of the cube.(V=s³)

• 27

• 9

• 18

Multiple Choice

The side of a cube is 6". Find the volume of the cube.(V=s³)

• 18

• 36

• 216

• 632

Multiple Choice

If s=5, evaluate 3s + 7

• 12

• 22

• 42

• 32

​Ready for some harder ones?

Multiple Choice

If x=2, a=3 and y=4

Evaluate

3x + 2a + 5y

Follow Order of Operations: Multiply First!

• 24

• 18

• 32

• 12

Multiple Choice

$$2x^2\ +2$$  

x=3

• 14

• 25

• 38

• 20

Multiple Choice

If a = 4 & b = 6, what is 3a + 5b?

• 40

• 42

• 44

• 46

Multiple Choice

Solve 14 - cd when c = 2 and d = 7

(side by side means multiply)

• 0

• 28

• 16

• 23