Question

Find $f\left(5\right)$ if $f\left(x\right)=x^2-3x$.

Short answer

The value of $f\left(5\right)$ is 10.

Step-by-step solution

– 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.

– Given information.

The given function is:

$f\left(x\right)=x^2-3x$

Substitute x=5 in the given function to find the value of $f\left(5\right)$.

$f\left(5\right)={\left(5\right)}^2-3\left(5\right)$

– Calculate the value by simplification.

$\begin{array}{c}f\left(5\right)={\left(5\right)}^2-3\left(5\right)\\ =25-15\\ =10\end{array}$

Thus,the value of $f\left(5\right)$ is 10.