After substituting, what is the first step when evaluating x+3x-4.2 when x= 5?
a. multiply 3 by 5
b. add 5 and 3
c. subtract 4.2 from 5
d. add 3 and 4.2.

After substitution, the first step when evaluating X + 3X - 4.2 when X=5, will be:

A. Multiply 3 by 5.

when X=5; X + 3X - 4.2 = 5 + 15 - 4.2

X + 3X - 4.2 = 15.8

Step-by-step explanation:

Because multiplication has priority in addition and subtraction.

MY ANSWER IS-9

Step-by-step explanation:

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