Answer:
About 4 hours.
Step-by-step explanation:
Let's set up a proportion and cross multiply.

Cross multiply.
120 = 28x
Divide by 28 on both sides.
= 4.28571428571
Round this to the nearest whole number, which is just 4. The answer is about 4 hours.
283 rounded to the nearest ten is 280
When rounding to the nearest ten look at the number to the right of the place you are rounding. In this case it is the 3. If the number is 5 or higher you go up to the nearest ten. If the number is lower than 5 like it is in this number you round down to the nearest ten.
Answer:
726.572699
Step-by-step explanation:
According to differentials
(x+Δx)³ = x³ + 3x²Δx + 3x(Δx)² + (Δx)³ (Using binomial expansion)
Using this formula to solve (8.99)³, this can also be written as;
(8.99)³ = (9-0.01)³ where
x = 9
Δx = -0.01
Substitute this vales into the differential expression above
(9+(-0.01))³ = 9³ + 3(9)²(-0.01) + 3(9)(-0.01)² + (-0.01)³
(9+(-0.01))³ = 729 + (243)(-0.01) + 27(0.0001) + (-0.000001)
(9+(-0.01))³ = 729-2.43+0.0027-0.000001
(9+(-0.01))³ = 729-2.43+0.0027-0.000001
(9+(-0.01))³ = 726.572699
Hence 8.99³ = 726.572699 (Using differential)
Using calculator;
8.99³ = 726.572699
Answer:
ummm where is the question anyway?
Answer:
C. -7x^2 - 28
Step-by-step explanation:
Firstly simplify the bracket before doing anything;
4x(3x - 7) = 12x^2 - 28x
then go back to the question and substitute the expression(12x^2 - 28x) on the bracket and then work out the question;
12x^2 - 28x -19x^2...then group the values with the same exponent of x,
(12x^2 - 19x^2) - 28x
; -7x^2 - 28x