Step-by-step explanation:
the average rate of change of a function f in an interval [x-low, x-high] is
(f(x-high) - f(x-low)) / (x-high - x-low)
the year 2000 means t = 2000-1980 = 20
the year 2015 means t = 2015-1980 = 35
so, we have
(A(35) - A(20)) / (35 - 20)
((-0.6(35)² + 37.2×35 + 243) - (-0.6(20)² + 37.2×20 + 243)) / 15
((-735 + 1302 + 243) - (-240 + 744 + 243)) / 15
(810 - 747) / 15 = 63/15 = 4.2
the average change rate between 2000 and 2015 is 4.2.
that means that the use of nuclear energy in the USA increased by 4.2 billions of kilowatt hours per year during that period.
Answer:

Step-by-step explanation:
Change the mixed number into a regular fraction.

Subtract the numerator.

As a mixed number:

Hello
sin ..... | 0° |30°|45°|60°|90°|
...........| 0...| 1..| 2..| 3..| 4..| write numbers
...........| 0...| 1..|√2.| √3 | 2..| take root square
...........| 0...|1/2|√2/2|√3/2|1| divide by 2
...........| 0...|1/2|√2/2|√3/2|1| .....
cos.....| 90°|60°|45°|30°| 0°|
sin (75°)
=sin(30°+45°)=sin 30°*cos 45° +cos 30°*sin 45°
.................... =1/2*√2/2 + √3/2*√2/2
.................... = √2(1+√3)/4
cos 75°
=cos(30°+45°)=cos 30°*cos 45°-sin 30°*cos 45°
=√3/2*√2/2-1/2*√2/2
=√6/4-√2/4=√2/4*(√3 -1 )
Answer:
Step-by-step explanation:
Subtraction is not commutative. For example, 4 − 7 does not have the same difference as 7 − 4. The − sign here means subtraction.
However, recall that 4 − 7 can be rewritten as 4 + (−7), since subtracting a number is the same as adding its opposite. Applying the commutative property for addition here, you can say that 4 + (−7) is the same as (−7) + 4. Notice how this expression is very different than 7 – 4.
Answer:
9x + 3 = 7x + 19
Step-by-step explanation:
Given that,
Jeffrey set up chairs for a meeting.
He arranged the chairs in 9 equal rows but had 3 chairs left over.
Let x be the number of chairs. So,
9x+3 .....(1)
Then he arranged the chairs in 7 equal rows but had 19 chairs left over. So,
7x+19 ......(2)
From equation (1) and (2),
9x+3 = 7x+19
9x-7x = 19-3
2x = 16
x = 8
Hence, the correct option is (b).