Question

Evaluate the expression when $x=4\text{and}y=2$

localid="1648624739300" $x^2-y$

Short answer

The value of the expression is14.

Step-by-step solution

Step-1 – Order of operations

To evaluate any expression involving more than one operation, follow the below order of operations:

• First evaluate expressions inside grouping symbols like parentheses ( ) or brackets [ ].
• Evaluate the exponents.
• Perform Multiplication and division from left to right.
• Perform addition and subtraction from left to right.

Step-2 – Evaluate the exponent

In order to evaluate the given expression, first substitute 4 for x and 2 for y and then expand the exponent as shown below

$\begin{array}{l}{x}^2-y\\ =4^2-2\\ =16-2\end{array}$

Step-3 – Subtract the numbers

Now to simplify further, subtract the resulting numbers to get

$\begin{array}{l}16-2\\ =14\end{array}$

Thus, the value of the expression is 14.