Step-by-step explanation:
f(x) = (x+7)(x-3)
= x²+4x-21 ... (option A)
You equation will be
2550 + (2550 X 8%)
2550 + (2550 X 0.08)
2550 + 204
= 2754
20/100 = 0.20
0.20 * 9 = 1.8
9 - 1.8 = 7.2
The sale price of the DVD is $7.20.
Question 1)
Volume of Tank A = Sum of volume of its two parts.
So,
Volume of Tank A = 24 + 96 = 120 cubic feet
Question 2)
Volume of Tank B and Tank A is the same. So, Volume of Tank B = 120 cubic feet
One section of Tank B = 45 cubic feet
So, volume of other section of tank B = 120 - 45 = 75 cubic feet
This is the number of combinations of 2 from 23
23C2 = 23! / 2! 21!
A quick way to do this is 23*22 / 2 = 253
