Answer:
-2, 8/3
Step-by-step explanation:
You can consider the area to be that of a trapezoid with parallel bases f(a) and f(4), and width (4-a). The area of that trapezoid is ...
A = (1/2)(f(a) +f(4))(4 -a)
= (1/2)((3a -1) +(3·4 -1))(4 -a)
= (1/2)(3a +10)(4 -a)
We want this area to be 12, so we can substitute that value for A and solve for "a".
12 = (1/2)(3a +10)(4 -a)
24 = (3a +10)(4 -a) = -3a² +2a +40
3a² -2a -16 = 0 . . . . . . subtract the right side
(3a -8)(a +2) = 0 . . . . . factor
Values of "a" that make these factors zero are ...
a = 8/3, a = -2
The values of "a" that make the area under the curve equal to 12 are -2 and 8/3.
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<em>Alternate solution</em>
The attachment shows a solution using the numerical integration function of a graphing calculator. The area under the curve of function f(x) on the interval [a, 4] is the integral of f(x) on that interval. Perhaps confusingly, we have called that area f(a). As we have seen above, the area is a quadratic function of "a". I find it convenient to use a calculator's functions to solve problems like this where possible.
Answer:
D
Step-by-step explanation:
Use the formula for the SA of a hemisphere.

Now we can find the radius of the hemisphere, which is 15.
Then, we can square that and multiply it by 2 to get 450.
Now, let's use the formula for the Volume of a hemisphere.

Now we can cube 15 and multiply it by 2 to get 6750.
Then we can divide this number by 3.
2250.
So the answer is D.
Answer:-43 + 9x = 0
Step-by-step explanation:Simplifying
9x + -43 = 0
Reorder the terms:
-43 + 9x = 0
Solving
-43 + 9x = 0
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '43' to each side of the equation.
-43 + 43 + 9x = 0 + 43
Combine like terms: -43 + 43 = 0
0 + 9x = 0 + 43
9x = 0 + 43
Combine like terms: 0 + 43 = 43
9x = 43
Divide each side by '9'.
x = 4.777777778
Simplifying
x = 4.777777778
B is your answer. Hope this helps :)
Answer:
409
Step-by-step explanation:
296 = 200 + 90 + 6
The value of the 9 is 90 in 296.
1/10 of 90 is 9. The only number that has a 9 in the units digit is 409.