What are you asking anyways hope you get a good grade
Add 2.2 to each side so 0.3z = 5.2 - 0.5z -0.8z
add 0.5z to each side so 0.8z = 5.2 - 0.8z
add 0.8z to each side so 1.4z = 5.2
divide each side by 1.4 so z = 3.71428571
The expression foiled together is 6(-3x^2+13xy-4y^2)
There are 720 total different combinations, and 24 of those will have the letters DAY consecutively within all those combinations.
<u>Explanation:</u>
FRIDAY is a six letter word.
To form all combinations of letters, we would have six choices of letters to fill the first spot. Whatever letter you choose for the first spot, you then have five choices of letters to fill the second spot. Four choices of letters to fill the third spot. And so on.
So, the total number of different combinations of the six letters would be 6!
6! = 6 X 5 X 4 X 3 X 2 X 1
= 720
DAY could appear consecutively starting in 4 different spots: the 1st, 2nd, 3rd, and 4th spots of all combinations. DAY will appear consecutively 6 times in each of those 4 starting spots.
6 X 4 = 24.
So, there are 720 total different combinations, and 24 of those will have the letters DAY consecutively within all those combinations.
If you would like to know how long will it take to drain the pool, you can calculate this using the following steps:
3 hours ... 250 gallons
x hours = ? ... 150 gallons (= 400 - 250)
3 * 150 = 250 * x
x = 3 * 150 / 250
x = 1.8 hours
3 hours + 1.8 hours = 4.8 hours
The correct result would be B. 4.8 hours.
