B. use the formula to solve 3x + 7 = 19 and
x - 1=5.

I'm not sure which formula to use because it's not indicated, but I'll just solve for x in both equations.

3x + 7 = 19

First I would subtract 7 on both sides:

3x = 12

Then I would divide 3 on both sides:

x = 4

x - 1 = 5

I would just add 1 on both sides:

x = 6

Hope I helped :)

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!

answer: 193

explanation:

200-7 = 193