Can you help me figure this out?

Question

I'm ot asking for answers but i need help. here is the problem:

Ramon rented a sprayer and a generator. On his first job, he used each piece of equipment for 6 hours at a total cost of $90. On his second job, he used the sprayer for 4 hours and the generator for 8 hours at a total cost of $100. What was the hourly cost of each piece of equipment?

PLEASE READ IT CAREFULLY!!!!! Thanx!

Answer 1

6S+6G=$90, S+G=$15
4S+8G=$100, S+2G=$25

Spray=$5/hr
Generator=$10/hr

Answer 2

6s + 6g = 90
4s + 8g = 100

multiply the 2 equations so that a term can be eliminated

12s + 12g = 180
12s + 24g = 300

subtract the two equations to define one term
12g = 120
g=10

substitute back to get the other term
6s + 60 =90
6s = 30
s = 5

The generator cost $10/hr, the sprayer cost $5/hr

Answer 3

You have two equations and two unknowns.

8g+4s=100
6g+6s=90

By solving the two you get that the sprayer is $5 per hour and the generator is $10 per hour.

Answer 4

S=sprayer
G=Generator

6(S+G)=90 first
4S+8G=100 second

from first
6(S+G)=90
S+G=90/6
S+G=15

S=15-G
G=15-S

combine with second

4S+8G=100 all divide by 4
S+2G=25 replace S with (15-G)
(15-G)+2G=25
15+G=25
G=25-15
G=10

or
S+2G=25 replace G with (15-S)
S+2(15-S)=25
S+(30-2S)=25
S+30-2S=25
-S=25-30
-S=-5
S=5

so the answer is
SPRAYER cost $5 per hour
GENERATOR cost $10 per hour