# Lesson 7

Using Factors and Zeros

- Let’s write some polynomials.

### Problem 1

Diego wrote \(f(x)=(x+2)(x-4)\) as an example of a function whose graph has \(x\)-intercepts at \(x=\text-4,2\). What was his mistake?

### Problem 2

Write a possible equation for a polynomial whose graph has horizontal intercepts at \(x=2,\text-\frac12,\text-3\).

### Problem 3

Which polynomial function’s graph is shown here?

A:

\(f(x)=(x+1)(x+3)(x+4)\)

B:

\(f(x)=(x+1)(x-3)(x+4)\)

C:

\(f(x)=(x-1)(x+3)(x-4)\)

D:

\(f(x)=(x-1)(x-3)(x-4)\)

### Problem 4

Which expression is equivalent to \((3x + 2)(3x - 5)\)?

A:

\(6x - 3\)

B:

\(9x^2 - 10\)

C:

\(9x^2 -3x - 10\)

D:

(From Unit 2, Lesson 4.)
\(9x^2-9x - 10\)

### Problem 5

What is the value of \(6(x-2)(x-3)+4(x-2)(x-5)\) when \(x=\text-3\)?

### Problem 6

Match each polynomial function with its leading coefficient.