Answer: x=- 8 or x=2
Step-by-step explanation:
1. To solve this problem you can applly the quadratic formula, which is shown below:

2. The quadratic equation is:

3. Then:
a=1
b=6
c=-16
4. Therefore, when you substitute these values into the quadratic formula, you obtain the following result:


Answer:
21 is 20% of 105
Step-by-step explanation:
20% * x = 21
20/100 * x = 21
x = 21 * 100/20
x = 105
If you are using a calculator, simply enter 21×100÷20, which will give you the answer.
So you need to divide 1000 by 125 which is 8. Which then you times by two to equal the two kilograms. So he needs to fill the cup up 16 times.
Answer:
5.5 minutes
Step-by-step explanation:
Fill in the given information and solve for t.
75 = -15cos(2πt/15) +65
-10/15 = cos(2πt/15)
t = 15/(2π)arccos(-2/3) ≈ 5.492
The volume reaches 75 dB about 5.5 minutes after the truck arrives.
B. (4, 4) is a solution to the equation.