The sum of two-sevenths of a number and 3 is 9. Can you please write out into an equation>~

The equation is: 2/7x + 3 = 9

The unknown number is: 21

Step-by-step explanation:

Write as an unknown value (using a variable)

2/7ths of a number = 2/7x

Write as an equation

2/7x + 3 = 9

Subtract 3 from both sides of the equation

2/7x = 6

Divide both sides of the equation by 2/7

x = 21

The equation is: 2/7x + 3 = 9

The unknown number is: 21

Hope this helps :)

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.

d. 145*2 is 290 than the total angle is 360 then minus 290 then divide by two