3x - 2y = 16 and x - 2y = 4 (any method <3)​

If Im supposed to use the substituiton method, please notify me!

1) 3x-2y=16

Divide each term  by 3 and simplify

divide each term in 3x=16 +2y by 3

3x/3=16/3+2y/3

Cancel the common factor of 3

3x/3(cross this fraction out)=16/3+2y/3

divide x by 1

x=16/3+2y/3

2) x-2y=4

Solve for x

1) Add 2y to both sides.

Solve for y

1) Subtract x from both sides.

2) Divide both sides by -2.

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.