Chapter SH, Problem 7.5.11EP

To determine

The sum or difference of given expression.

Answer to Problem 7.5.11EP

  $8x^2+5xy-15y^2$

Explanation of Solution

Given:

The given expression is:

  $\left(9x^2-11xy-3y^2\right)-\left(x^2-16xy+12y^2\right)$

Calculation:

The sum or difference of the given expression can be calculated as:

  $\begin{array}{l}=\left(9x^2-11xy-3y^2\right)-\left(x^2-16xy+12y^2\right)\\ =\left(9x^2-x^2\right)+\left(-11xy-\left(-16xy\right)\right)+\left(-3y^2-12y^2\right)\\ =\left(8x^2\right)+\left(5xy\right)+\left(-15y^2\right)\\ =8x^2+5xy-15y^2\end{array}$