Justin is evaluating the expression 12.5 + 3.8 x, when x is 7.9. 12.5 + 3.8 (7.9). 16.3 (7.9). 128.77. What was Justin's error? Justin should have multiplied 12.5 and 7.9 first. Justin should have added 12.5 and 7.9 first. Justin should have multiplied 3.8 and 7.9 first. Justin should have added 3.8 and 7.9 first.

Justin should have multiplied 3.8 and 7.9 first.

Step-by-step explanation:

Given the equation

12.5 + 3.8x

where, x = 7.9, the first thing that Justin's should have done was to multiply 3.8 and 7.9 first. This will be:

= 12.5 + 3.8x.

= 12.5 + 3.8(7.9)

= 12.5 + 30.02

= 42.52

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!

b

step-by-step explanation: