Combining Functions
Function Type
Given Inputs
Given Outputs
100

f(x) = x + 1               g(x) = x + 1

(f + g)(x)?

(f + g)(x) = 2x + 2

100

Linear, Quadratic, or Non-Polynomial?

Linear Polynomial Function

100

f(x) = x + 3

f(2) = ?

f(2) = 2 +3

f(2) = 5

100

f(x) = x + 3

What is x when f(x) is 8?

When f(x) = 8,

8 = x + 3

x = 5

200

f(x) = x + 1          g(x) = x + 2

(f + g)(x)?

(f + g)(x) = 2x + 3

200

Linear, Quadratic, or Non-Polynomial?

Quadratic Polynomial Function

200

f(x) = x + 5

f(5) = ?

f(5) = 5 + 5

f(5) = 10

200

f(x) = x + 5

What is x when f(x) = 10?

When f(x) = 10,

10 = x + 5

x = 5

300

f(x) = x + 3          g(x) = x + 5

(f + g)(x)?

(f + g)(x) = 2x + 8

300

Linear, Quadratic, or Non-Polynomial Function?

Non-Polynomial Function

300

f(x) = 2x

f(3) = ?

f(3) = 2(3)

f(3) = 6

300

f(x) = 2x

What is x when f(x) = 10?

When f(x) = 10,

10 = 2x

x = 5

400

f(x) = 2x + 3           g(x) = x + 1

(f + g)(x)?

(f + g)(x) = 3x + 4

400

3x + 2

Linear, Quadratic, or Non-Polynomial Function?

Linear Function

400

f(x) = 2x + 1

f(2) = ?

f(2) = 2(2) +1

f(2) = 4 +1

f(2) = 5

400

f(x) = 2x + 1

What is x when f(x) is 11?

When f(x) = 11,

11 = 2x + 1

10 = 2x

x = 5

500

f(x) = 2x + 5          g(x) = x -1

(f + g)(x)?

(f + g)(x) = 3x + 4

500

x2 + 5x + 6

Linear, Quadratic, or Non-Polynomial Function?

Quadratic Function

500

(f + g)(x) = 3x + 6

(f + g)(10) = ?

(f + g)(x) = 3(10) + 6

(f + g)(x) = 30 + 6

(f + g)(x) = 36

500
(f + g)(x) = 3x + 6

What is x when (f + g)(x) = 21?

When (f + g)(x) = 21,

21 = 3x + 6

15 = 3x

X = 5

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