Question
upstudy study bank question image url

Use synthetic division to divide the polynomials \[ \left(4 x^{2}+20 x+20\right) \div(x+9) \]

Ask by Mccoy Spencer. in the United States
Mar 15,2025

Upstudy AI Solution

Tutor-Verified Answer

Answer

The result of the division is \(4x - 16\) with a remainder of 164.

Solution

**Step 1.** Recognize that the divisor is in the form \( x+9 \), which can be written as \( x-(-9) \). Thus, we will use \(-9\) as our synthetic division number. **Step 2.** Write down the coefficients of the dividend polynomial \( 4x^2 + 20x + 20 \): \[ 4,\quad 20,\quad 20. \] **Step 3.** Set up the synthetic division: \[ \begin{array}{r|ccc} -9 & 4 & 20 & 20 \\ & & & \\ \hline & 4 & & \end{array} \] 1. **Bring down** the first coefficient \(4\). \[ \begin{array}{r|ccc} -9 & 4 & 20 & 20 \\ & & & \\ \hline & 4 & & \end{array} \] 2. **Multiply** \(4\) by \(-9\) to get \(-36\), and write it under the second coefficient: \[ \begin{array}{r|ccc} -9 & 4 & 20 & 20 \\ & & -36 & \\ \hline & 4 & & \end{array} \] 3. **Add** the second coefficient \(20\) and \(-36\): \[ 20 + (-36) = -16. \] Write \(-16\) below the line: \[ \begin{array}{r|ccc} -9 & 4 & 20 & 20 \\ & & -36 & \\ \hline & 4 & -16 & \end{array} \] 4. **Multiply** \(-16\) by \(-9\) to get \(144\), and write it under the third coefficient: \[ \begin{array}{r|ccc} -9 & 4 & 20 & 20 \\ & & -36 & 144 \\ \hline & 4 & -16 & \end{array} \] 5. **Add** the third coefficient \(20\) and \(144\): \[ 20 + 144 = 164. \] Write \(164\) below the line: \[ \begin{array}{r|ccc} -9 & 4 & 20 & 20 \\ & & -36 & 144 \\ \hline & 4 & -16 & 164 \end{array} \] **Step 4.** Interpret the result: - The numbers \(4\) and \(-16\) represent the coefficients of the quotient polynomial \( 4x - 16 \). - The last number, \(164\), is the remainder. Thus, the division can be expressed as: \[ 4x^2 + 20x + 20 = (x+9)(4x - 16) + 164. \]

Answered by UpStudy AI and reviewed by a Professional Tutor

error msg
Explain
Simplify this solution

Beyond the Answer

To divide the polynomial \( 4x^2 + 20x + 20 \) by \( x + 9 \) using synthetic division, we first set \( x + 9 = 0 \) to find the root, which is \( x = -9 \). Now, we will arrange the coefficients of the polynomial \( 4x^2 + 20x + 20 \), which are \( 4, 20, 20 \). Next, we perform synthetic division: 1. Write \( -9 \) on the left and the coefficients on the right: \[ \begin{array}{r|rrr} -9 & 4 & 20 & 20 \\ \end{array} \] 2. Bring down the leading coefficient (4): \[ \begin{array}{r|rrr} -9 & 4 & 20 & 20 \\ & & & \\ & 4 & & \\ \end{array} \] 3. Multiply \( -9 \) by \( 4 \) and write it under the next coefficient (20): \[ \begin{array}{r|rrr} -9 & 4 & 20 & 20 \\ & & -36 & \\ & 4 & & \\ \end{array} \] 4. Add \( 20 + (-36) = -16 \): \[ \begin{array}{r|rrr} -9 & 4 & 20 & 20 \\ & & -36 & \\ & 4 & -16 & \\ \end{array} \] 5. Multiply \( -9 \) by \( -16 \) and write it under the next coefficient (20): \[ \begin{array}{r|rrr} -9 & 4 & 20 & 20 \\ & & -36 & 144 \\ & 4 & -16 & \\ \end{array} \] 6. Add \( 20 + 144 = 164 \): \[ \begin{array}{r|rrr} -9 & 4 & 20 & 20 \\ & & -36 & 144 \\ & 4 & -16 & 164 \\ \end{array} \] The final row gives us the coefficients of the quotient and the remainder. Thus, we have: - Quotient: \( 4x - 16 \) - Remainder: \( 164 \) Therefore, the result of the division is: \[ 4x - 16 + \frac{164}{x + 9} \]

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy