Question

Evaluate the expression when $x=6\text{and}y=12$. (Lesson 1.3)

localid="1647503467763" $3\left(x+y\right)$

Short answer

The value of the expression is54.

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 expression inside grouping symbol

To evaluate the expression $3\left(x+y\right)$, substitute 6 for x and 12 for y in the given expression and simplify the expression inside the parenthesis as follows

$\begin{array}{c}3\left(x+y\right)=3\left(6+12\right)\\ =3\left(18\right)\end{array}$

Step-3 – Multiply the numbers

Now to simplify further, Multiply the numbers to get

$\begin{array}{c}3\left(x+y\right)=3\left(18\right)\\ =3\cdot 18\\ =54\end{array}$

Thus, the value of the expression is 54.