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.

what's that

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.