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Practice · A.1.e

Evaluate polynomials

Question 1 of 36 · 0 right

Question 1 of 36

No calculator

What is the value of x^2 + 3x - 4 when x = 3?

Answer choices
Hint

Square 3 first (3 \cdot 3), then multiply 3 \cdot 3 for the middle term, then add and subtract.

Question 2 of 36

No calculatorFill in

Evaluate 2x^2 - 5 when x = -3.

Type your answer in the box. Fractions like 3/4 are fine.

Hint

Square -3 first. A negative number times itself is positive. Then multiply by 2.

Question 3 of 36

No calculator

What is the value of -x^2 + 4x when x = -2?

Answer choices
Hint

In -x^2, square x first, then take the opposite. Watch the sign of 4x too.

Question 4 of 36

No calculator

If x = 3, what number does x^4 - 3x^2 + 2x equal?

Answer choices
Hint

Find each power first: 3^4 and 3^2. Then multiply by the coefficients, then add and subtract from left to right.

Question 5 of 36

Fill in

Find 6x^2 - 5x + 1 for x = \tfrac{1}{2}. Enter your answer as a number.

Type your answer in the box. Fractions like 3/4 are fine.

Hint

Square the fraction first: \left(\tfrac{1}{2}\right)^2 = \tfrac{1}{4}. You may switch to decimals: \tfrac{1}{2} = 0.5.

Question 6 of 36

No calculator

Substitute x = -2 into x^3 - 2x^2 + 5. What is the result?

Answer choices
Hint

(-2)^3 has three negative factors, and (-2)^2 has two. Decide each sign before you combine.

Question 7 of 36

No calculator

The table shows some values of p(x) = 2x^2 - x - 3.

x-2-1012
p(x)70-3?3

What is the missing value p(1)?

Answer choices
Hint

Do not guess from the pattern. Substitute x = 1 into the formula.

Question 8 of 36

A ball is thrown upward from a balcony. Its height, in feet, after t seconds is given by

h = -16t^2 + 64t + 5

What is the height of the ball after 1.5 seconds?

Answer choices
Hint

Square 1.5 first, then multiply by -16. Do not square the -16.

Question 9 of 36

Fill in

Evaluate 3x^3 - 2x^2 + x - 7 when x = 2.

Type your answer in the box. Fractions like 3/4 are fine.

Hint

Find 2^3 and 2^2 first. Then multiply by the coefficients.

Question 10 of 36

Drop-down

Select the value that makes the statement true.

When a = 5 and b = -1, the value of a^2 - 2ab + b^2 is .

Choose an answer from each menu.

Hint

Find each of the three terms separately: a^2, then -2ab, then b^2. Count the negative signs in -2ab.

Question 11 of 36

A small business models its weekly revenue, in dollars, with the formula

R = -2p^2 + 120p

where p is the price of its product in dollars. What is the weekly revenue when the price is $25?

Answer choices
Hint

Square 25 first, then multiply by -2. Find 120 \times 25, then combine.

Question 12 of 36

An open box is made from a 10-inch by 8-inch sheet of cardboard by cutting an x-inch square from each corner and folding up the sides.

A rectangular sheet 10 inches by 8 inches with an x-by-x inch square cut from each of its four corners. Dashed lines show where the sides fold up to make an open box with height x, length 10 - 2x and width 8 - 2x.10 in8 inxbaseCut an x-by-x square from each corner, fold up the sides

The volume of the box, in cubic inches, is V = x(10 - 2x)(8 - 2x). What is the volume when x = 1.5?

Answer choices
Hint

Find each factor first: the height x, the length 10 - 2x and the width 8 - 2x. Then multiply all three.

Question 13 of 36

Select all

Select all polynomials that have a value of 0 when x = -1.

Select all that apply.

Answer choices
Hint

Use (-1)^2 = 1 and (-1)^3 = -1. Evaluate each choice carefully.

Question 14 of 36

A model rocket is launched straight up from the ground. Its height, in feet, after t seconds is

h = -16t^2 + 96t

What is the height of the rocket after 2.5 seconds?

Answer choices
Hint

Square 2.5 first (it is not 4.25). Then multiply by -16 and add 96 \cdot 2.5.

Question 15 of 36

No calculator

Jordan evaluated -3x^2 + 2x when x = -4. His work is shown.

StepWork
1-3(-4)^2 + 2(-4)
2-3(16) + (-8)
348 - 8
440

In which step did Jordan make his first error?

Answer choices
Hint

Check the square in Step 2, then check the sign of each product in Step 3.

Question 16 of 36

Fill in

Evaluate 3m^2n - mn^2 + 4 when m = 2 and n = -3.

Type your answer in the box. Fractions like 3/4 are fine.

Hint

Write each term with the numbers in parentheses: 3(2)^2(-3), then (2)(-3)^2. Find the powers first.

Question 17 of 36

A spreadsheet cell computes 2x^3 - x. What value does it return for the input x = 0.5?

Answer choices
Hint

0.5^3 = 0.5 \cdot 0.5 \cdot 0.5. A number between 0 and 1 gets smaller when you raise it to a power.

Question 18 of 36

A bakery estimates its monthly cost, in dollars, of baking x dozen bagels with

C = 0.05x^2 - 3x + 400

What is the estimated monthly cost when the bakery bakes 120 dozen bagels?

Answer choices
Hint

Square 120 first, then multiply by 0.05. Keep the minus sign on the 3x term.

Question 19 of 36

Fill in

A storage box has a square base with sides of x inches and a height of 5 inches. Its total surface area, in square inches, is

S = 2x^2 + 20x

What is the surface area when x = 4.5 inches?

square inches

Type your answer in the box. Fractions like 3/4 are fine.

Hint

Square 4.5 first. Then double it, and add 20 \times 4.5.

Question 20 of 36

The population of a town, in thousands, t years after 2010 is modeled by

P = 0.2t^2 + 3t + 50

By how many thousand people does the model say the population increased from 2015 (t = 5) to 2020 (t = 10)?

Answer choices
Hint

Find P at t = 10 and at t = 5 separately, then subtract. Do not plug in 10 - 5.

Question 21 of 36

Fill in

The function f(x) = ax^2 - 5x + 2 has an unknown coefficient a. A table shows that f(-2) = 24. Find a.

a =

Type your answer in the box. Fractions like 3/4 are fine.

Hint

Substitute x = -2 into the formula, keep a as a letter, and set the result equal to 24.

Question 22 of 36

Drop-down

Complete the table of values for q(x) = x^3 - x^2 - 4.

x-1023
q(x)-40

Choose an answer from each menu.

Hint

For x = -1: (-1)^3 = -1 and (-1)^2 = 1. For x = 3: 3^3 = 27 and 3^2 = 9.

Question 23 of 36

Select all

Which polynomials equal 10 at x = 2? Choose every polynomial that works.

Select all that apply.

Answer choices
Hint

Evaluate every choice at x = 2; more than one is correct. Use 2^2 = 4 and 2^3 = 8.

Question 24 of 36

Fill in

A diver jumps from a platform. Her height above the water, in feet, t seconds after she jumps is

h = -16t^2 + 8t + 32

What is her height above the water after 1.25 seconds?

feet

Type your answer in the box. Fractions like 3/4 are fine.

Hint

Find (1.25)^2 first. Then multiply by -16, add 8 \times 1.25, and add 32.

Question 25 of 36

Fill in

For the polynomial p(x) = x^2 + kx - 6, the value p(3) = 12.

What is the value of k?

k =

Type your answer in the box. Fractions like 3/4 are fine.

Hint

p(3) means substitute x = 3. Set the result equal to 12 and solve for k.

Question 26 of 36

What is the value of 2x^2y - 3xy^2 + y^3 when x = -2 and y = 3?

Answer choices
Hint

Evaluate each term on its own. In x^2y only x is squared; in xy^2 only y is squared.

Question 27 of 36

Priya evaluated x^2 - 3xy + y^2 when x = -1 and y = 4. Her work is shown.

StepWork
1(-1)^2 - 3(-1)(4) + (4)^2
2-1 + 12 + 16
327

Which statement correctly describes Priya's work?

Answer choices
Hint

Check each part of Step 2 separately: (-1)^2, then -3(-1)(4), then (4)^2.

Question 28 of 36

A theater's ticket revenue, in dollars, is modeled by

R = p(200 - 4p)

where p is the ticket price in dollars. What is the revenue when tickets cost $18.50?

Answer choices
Hint

Work inside the parentheses first: 200 - 4(18.50). Then multiply the result by 18.50.

Question 29 of 36

The area, in square feet, of a rectangular garden that is x feet wide is given by A = x^2 + 4x. For what width x is the area 45 square feet?

Answer choices
Hint

Try each answer choice: substitute it for x and see which one gives exactly 45.

Question 30 of 36

A company designs cylindrical cans whose height is always 3 inches more than the radius. The volume of a can with radius r inches is

V = \pi r^3 + 3\pi r^2

What is the volume, in cubic inches, of a can with a radius of 4 inches? Leave your answer in terms of \pi.

Answer choices
Hint

Find 4^3 and 4^2 first. Then add the two terms; both contain \pi, so you can add their coefficients.

Question 31 of 36

Fill in

Let g(x) = 9x^2 - 6x + 4. What is g\left(-\tfrac{2}{3}\right)?

Type your answer in the box. Fractions like 3/4 are fine.

Hint

\left(-\tfrac{2}{3}\right)^2 = \tfrac{4}{9} (positive). Watch the sign of -6 \cdot \left(-\tfrac{2}{3}\right).

Question 32 of 36

Drag and drop

Drag a value into each empty box to complete the table for f(x) = -x^2 + 3x + 1. Not every tile is used.

x-2024
f(x)

Tap a tile, then tap a box to place it.

Hint

-x^2 means "square x, then take the opposite". So -x^2 is negative (or zero) for every x.

Question 33 of 36

A company's weekly profit, in dollars, from making x chairs is

P = -0.5x^2 + 40x - 350

How much more profit does the company make in a week when it makes 40 chairs than when it makes 30 chairs?

Answer choices
Hint

Evaluate the profit at x = 40 and at x = 30, then subtract.

Question 34 of 36

Two print shops price a custom order of x posters differently:

  • Shop A: C_A = 0.02x^2 + 5x + 100 dollars
  • Shop B: C_B = 8x + 40 dollars

For an order of 150 posters, which shop is cheaper, and by how much?

Answer choices
Hint

Evaluate both formulas at x = 150. Square 150 before multiplying by 0.02. Then subtract the smaller cost from the larger.

Question 35 of 36

Select all

Let p(x) = x^3 - 4x^2 + x + 6. Select all true statements.

Select all that apply.

Answer choices
Hint

Compute p(-2), p(-1), p(0), p(1), p(2), p(3) and p(4) as needed. Keep negatives in parentheses.

Question 36 of 36

Drop-down

In a science lab, the height in meters of a ball thrown upward is h = -4.9t^2 + 20t + 1.5, where t is the time in seconds. Sam found the height at t = 3:

StepWork
1-4.9(3)^2 + 20(3) + 1.5
2-4.9(9) + 60 + 1.5
344.1 + 60 + 1.5
4105.6

Sam's first error is in . The correct height at t = 3 is meters.

Choose an answer from each menu.

Hint

Check the sign of -4.9 \times 9 in Step 3.