{7x^2+2x-9}/{7x+9}+(x+2)(x-3) simplify

1 answer

To simplify the expression \(\frac{7x^2 + 2x - 9}{7x + 9} + (x + 2)(x - 3)\), we can follow these steps:

Step 1: Simplify the second term

First, simplify \((x + 2)(x - 3)\):

\[ (x + 2)(x - 3) = x^2 - 3x + 2x - 6 = x^2 - x - 6 \]

Step 2: Combine the terms

Now we can rewrite the expression as:

\[ \frac{7x^2 + 2x - 9}{7x + 9} + x^2 - x - 6 \]

Step 3: Prepare to combine the fractions

To combine these, we need a common denominator, which is \(7x + 9\). Rewrite the second term with the common denominator:

\[ x^2 - x - 6 = \frac{(x^2 - x - 6)(7x + 9)}{7x + 9} \]

Step 4: Expand \(x^2 - x - 6\) with the denominator

Now, let's expand \((x^2 - x - 6)(7x + 9)\):

\[ = (x^2)(7x + 9) + (-x)(7x + 9) + (-6)(7x + 9) \] \[ = 7x^3 + 9x^2 - 7x^2 - 9x - 42x - 54 \] \[ = 7x^3 + 2x^2 - 51x - 54 \]

Step 5: Write combined fraction

Now, we can write our entire expression with the common denominator:

\[ \frac{7x^2 + 2x - 9 + 7x^3 + 2x^2 - 51x - 54}{7x + 9} \]

Step 6: Combine like terms in the numerator

Combine all of the terms in the numerator:

  1. The \(x^3\) term: \(7x^3\)
  2. The \(x^2\) terms: \(2x^2 + 2x^2 = 4x^2\)
  3. The \(x\) terms: \(2x - 51x = -49x\)
  4. The constant terms: \(-9 - 54 = -63\)

So the numerator is:

\[ 7x^3 + 4x^2 - 49x - 63 \]

Step 7: Final result

Putting the expression back together, we have:

\[ \frac{7x^3 + 4x^2 - 49x - 63}{7x + 9} \]

This is the simplified form of the original expression. Further simplification (like factoring) would depend on the specific goals, but for now, this is an acceptable simplified form.