Use long division to divide the polynomial 15x2+14x−8 by 3x+4. What is the quotient?(1 point)Responses5x+2−163x+45 x plus 2 minus Start Fraction 16 over 3 x plus 4 End Fraction5x−2+163x+45 x minus 2 plus Start Fraction 16 over 3 x plus 4 End Fraction5x−25 x minus 25x+2

1 answer

To divide the polynomial \( 15x^2 + 14x - 8 \) by \( 3x + 4 \) using long division, let's go through the steps:

  1. Setup the long division: \[ \text{Divide: } 15x^2 + 14x - 8 \div (3x + 4) \]

  2. Divide the leading term: Divide the leading term of the dividend \( 15x^2 \) by the leading term of the divisor \( 3x \): \[ \frac{15x^2}{3x} = 5x \]

  3. Multiply and subtract: Multiply \( 5x \) by \( 3x + 4 \): \[ 5x(3x + 4) = 15x^2 + 20x \]

    Subtract this product from the original polynomial: \[ (15x^2 + 14x - 8) - (15x^2 + 20x) = 14x - 20x - 8 = -6x - 8 \]

  4. Repeat the process: Now take the leading term \(-6x\) and divide it by \(3x\): \[ \frac{-6x}{3x} = -2 \]

  5. Multiply and subtract again: Multiply \(-2\) by \(3x + 4\): \[ -2(3x + 4) = -6x - 8 \]

    Subtract this from \(-6x - 8\): \[ (-6x - 8) - (-6x - 8) = 0 \]

  6. Conclusion: The result of the division is: \[ 5x - 2 \] with a remainder of 0. Thus, the quotient of the division \( 15x^2 + 14x - 8 \div (3x + 4) \) is: \[ \boxed{5x - 2} \]