Question

(x+3)(3x² - 5x - 10) multiply polynomial

Answer 1

`3x^2 + 4x^2 - 25x - 30`

Explanation:

Step 1: Distribute

`(x + 3)(3x^2 - 5x - 10)`

`(x * 3x^2) + (x * (-5x)) + (x * (-10)) + (3 * 3x^2) + (3 * (-5x)) + (3 * (-10))`

`3x^3 - 5x^2 - 10x + 9x^2 - 15x - 30`

Step 2: Combine like terms

`3x^3 - 5x^2 + 9x^2 - 15x - 10x - 30`

`(3x^2) + (-5x^2 + 9x^2) + (-15x - 10x) + (-30)`

`3x^2 + 4x^2 - 25x - 30`

Answer:
`3x^2 + 4x^2 - 25x - 30`

Answer 2

• 
  `\boxed{\sf{3x^3+4x^2-25x-30}}`

Explanation:

`\underline{\text{SOLUTION:}}`

To isolate the term of x from one side of the equation, you must multiply by a polynomial.

`\underline{\text{GIVEN:}}`

`:\Longrightarrow: \sf{(x+3)(3x^2 - 5x - 10)}`

You have to solve with parentheses first.

`:\Longrightarrow \sf{x\cdot \:3x^2+x\left(-5x\right)+x\left(-10\right)+3\cdot \:3x^2+3\left(-5x\right)+3\left(-10\right)}`

Solve.

`\sf{x*3x=3x^3}`

x(-5x)=-5x²

`\sf{x(-10)=-10x}`

3*3x²=9x²

3(-5x)=-15x

3(-10)=-30

Then, rewrite the problem down.

`\sf{3x^3-5x^2-10x+9x^2-15x-30}`

Combine like terms.

`\Longrightarrow: \sf{3x^3-5x^2+9x^2-10x-15x-30}`

Add/subtract the numbers from left to right.

-5x²+9x²=4x²

`\Longrightarrow: \sf{3x^3+4x^2-10x-15x-30}`

Solve.

`\sf{-10x-15x=-25x}`

Then rewrite the problem.

`\Longrightarrow: \boxed{\sf{3x^3+4x^2-25x-30}}`

• Therefore, the correct answer is 3x³+4x²-25x-30.

I hope this helps! Let me know if you have any questions.