Question

evaluate the expression when ( y = 3 ) and ( x = 17 ).
( x - 5y )
explanation
we replace ( y ) with 3 and ( x ) with 17.
( x - 5y )
( 17 - 5(3) )
what do ( 5y ) and ( 5(3) ) mean?
then, we use the order of operations to get our answer
( 17 - 5(3) )

Explanation:

Step1: Substitute values

Substitute \(x = 17\) and \(y = 3\) into the expression \(x - 5y\). We get \(17-5\times3\).

Step2: Perform multiplication

According to the order of operations (PEMDAS/BODMAS, where multiplication comes before subtraction), calculate \(5\times3\).
\(5\times3=15\).

Step3: Perform subtraction

Now, subtract the result of the multiplication from 17. So, \(17 - 15\).
\(17-15 = 2\).

Answer:

\(2\)

Regarding the question in the orange box "What do \(5y\) and \(5(3)\) mean?":

• \(5y\) means \(5\) multiplied by the variable \(y\). In algebra, when a number is adjacent to a variable (with no operation sign in between, except in the case of subtraction/ addition which is indicated by a sign), it represents multiplication.
• \(5(3)\) means \(5\) multiplied by \(3\). The parentheses here are just used to denote multiplication (it's an alternative notation to \(5\times3\)).