The length of a rectangle is 19 centimeters less than its width. Its area is 20 square centimeters. Find the dimensions of the rectangle. Use the​ formula, area =length*width.

width =20

length = 1

Step-by-step explanation:

length = w - 19

A = l*w

20 = (w-19) * w

20 = w^2 - 19w

Subtract 20 from each side

0 = w^2 - 19w - 20

Factor

0 = (w+1)(w-20)

Using the zero product property

w+1 = 0 w-20 = 0

w = -1   w=20

Widths cannot be negative

w=20

l = 20-19 = 1

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.

-2 is the right