Simplify completely quantity x squared plus 12 x plus 35 all over 3 x plus 15.

quantity of x squared plus 21 over 3
quantity of x squared plus 11 over 3
quantity x plus 7 over 3
quantity of x plus 5 over 3

1 answer

To simplify the expression \(\frac{x^2 + 12x + 35}{3x + 15}\), we will first factor both the numerator and the denominator.

  1. Factor the numerator \(x^2 + 12x + 35\): We look for two numbers that multiply to \(35\) (the constant term) and add to \(12\) (the coefficient of \(x\)). The numbers \(5\) and \(7\) work because: \[ 5 \times 7 = 35 \quad \text{and} \quad 5 + 7 = 12. \] Thus, we can factor the numerator as: \[ x^2 + 12x + 35 = (x + 5)(x + 7). \]

  2. Factor the denominator \(3x + 15\): We can factor out a \(3\): \[ 3x + 15 = 3(x + 5). \]

  3. Rewrite the original expression using the factored forms: \[ \frac{x^2 + 12x + 35}{3x + 15} = \frac{(x + 5)(x + 7)}{3(x + 5)}. \]

  4. Cancel the common factor \((x + 5)\), assuming \(x \neq -5\): \[ = \frac{x + 7}{3}. \]

Thus, the simplified form of your original expression is: \[ \frac{x + 7}{3}. \]

Final Answer: \(\frac{x + 7}{3}\)