The sum of two numbers is 37 and the difference is 13 . what are the numbers?

25, 12

Step-by-step explanation:

let x represent one number and y represent the other number

x+y=37    (sum is addition)

x-y=13      (difference is subtraction)

Im solving using the substitution method

x-y=13 add y to both sides to get x by itself

x=13+y

13+y+y=37 substitute x for the solution above in the other equation and simplify

2y=24

y=12

plug in y into one of the equations

x+12=37 subtract 12 from both sides

x=25

do i do it on a graph?

step-by-step explanation:

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.