Chapter 8.2, Problem 96CCR

To determine

The solution of the expression $xy-y$ ,

Answer to Problem 96CCR

The solution of the expression is $-30$ .

Explanation of Solution

Given:

The expression, $xy-y$ .If $x=4,y=-10,\text{and z}=14$

Concept Used:

• To get rid of a number in addition from one side, subtract the same number from both sides of equal sign.
• To get rid of a number in subtraction from one side, add the same number both sides of equal sign.
• To get rid of a number in multiplication from one side, divide the same number from both sides of equal sign.
• To get rid of a number in division from one side, multiply the same number both sides of equal sign.

Rules of Addition/ Subtraction:

• Two numbers with similar sign always get added and the resulting number will carry the similar sign.
• Two numbers with opposite signs always get subtracted and the resulting number will carry the sign of larger number.

Rules of Multiplication/ Division:

• The product/quotient of two similar sign numbers is always positive.
• The product/quotient of two numbers with opposite signs is always negative.

Calculation:

In order to solve the given expression $xy-y$ put the values $x=4,y=-10,\text{and z}=14$ in the given expression and then simplify further as shown below,

  $\begin{array}{c}xy-y=4\times \left(-10\right)-\left(-10\right)\\ =-40+10\\ =-30\end{array}$

Thus, the solution of the expression is $-30$ .