Find the value of X
please help!

Step-by-step explanation:

So the first thing to do is get the number of angles inside this pentagon, which is 540 degrees. One way to do this is that you know a pentagon is formed of 3 triangles and since there are 180 degrees in a triangle, 3x180=540

Then it is algebra

540=91+125+92+(3x-5)+(4x-8)

Simplify what you can and collect like terms

540=308+3x-5+4x-8

540=308+7x-13

Then move everything over to the one side so that the variable is isolated

540-308+13=7x

245=7x

242/7=x

35=x

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.