Answer:
B
Step-by-step explanation:
To find f(- 2) substitute x = - 2 into f(x)
f(- 2) = - 2(- 2)³ + (- 2)² + 4(- 2) - 3
= - 2(- 8) + 4 - 8 - 3
= 16 + 4 - 8 - 3
= 9 → B
Answer:
20ln(3)
Step-by-step explanation:
Put 15 for A and solve for t.
15 = 45e^(-.05t)
15/45 = 1/3 = e^(-.05t) . . . . divide by 45
ln(1/3) = -.05t . . . . . . . . . . . take natural logs
20ln(3) = t . . . . . . . . . . . . . . multiply by 20, simplify
It will take 20·ln(3) years for the area to decrease to 15 km^2.
Width-24 Length-29
Two sides of the rectangle are 5 cm bigger than the other two. So you would add the two 5 cm together (10cm). If you take the 10 cm off you (106-10) you will get a square. Then all you have to do is divide 96 by 4 (24), and add back on the two 5cm from the beginning to the length (29).
Answer:
A.
Step-by-step explanation:
x2 - 3x - 10. = 0
x2 + 2x - 5x - 10 = 0
(x2 + 2x) (-5x - 10) = 0
x (x + 2) - 5 (x + 2) = 0
(x - 5) (x + 2) = 0
x - 5 = 0 x + 2 = 0
x = 5 or x = - 2.
To solve this problem we will start by calculating time needed for each of them to fill the pool.
We have formula:
Volume = rate * time
Or
time = volume / rate
Wilma:
time = 9900 / 900
time = 11h
Betty:
time = 9900 / 500
time = 19.8h
Now we substract these two numbers:
time_difference = 19.8 - 11 = 8.8h
Betty needs 8.8 hours more than Wilma to fill the pool.
