There are two ways to do this
Method 1:
Find (fg)(x) first
(fg)(x) = f(x)*g(x)
(fg)(x) = (x^2-19)*(20-x)
(fg)(x) = 20x^2-x^3-380+19x
(fg)(x) = -x^3+20x^2+19x-380
Then plug in x = -10
(fg)(x) = -x^3+20x^2+19x-380
(fg)(-10) = -(-10)^3+20(-10)^2+19(-10)-380
(fg)(-10) = -(-1000)+20(100)+19(-10)-380
(fg)(-10) = 1000+2000-190-380
(fg)(-10) = 3000-570
(fg)(-10) = 2430
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Method 2:
Find f(-10)
f(x) = x^2 - 19
f(-10) = (-10)^2 - 19
f(-10) = 100 - 19
f(-10) = 81
Find g(-10)
g(x) = 20-x
g(-10) = 20-(-10)
g(-10) = 20+10
g(-10) = 30
Multiply the two results
(fg)(-10) = f(-10)*g(-10)
(fg)(-10) = 81*30
(fg)(-10) = 2430
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Whichever method you pick, the answer is: 2430
Answer:
3x ≤ 12 x≤4
Step-by-step explanation:
If Antonio has only $12 to spend on the milk, then the inequality sign should be less than or equal to. Since he can not go over 12. So from this you must figure out how many cartons he can buy. 12/3 = 4. So the maximum amount he can buy is 4 cartons.
Answer:
x = 35 degrees
Step-by-step explanation:
∠BCA = ∠DAF because they are corresponding angles.
∠BCA + 42 + 103 = 180 (angles in a triangle = 180)
∠BCA = 180 - (42+103)
∠BCA = 35
∠BCA = x (corresponding angles)
x = 35
28 - 51 = 23
your andwer is 23
The answer is: The surface area of the sphere.
The explanations for this exercise is shown below:
By definition, the surface area of a sphere is four times the area of a circle.
You have that the area of a circle is:
![A=\pi r^{2}](https://tex.z-dn.net/?f=%20A%3D%5Cpi%20r%5E%7B2%7D%20%20)
Where
is the radius of the circle.
Therefore, to calculate the surface area of a sphere with radius
, you only need to multiply the equation shown above by four, as following:
![SA=4\pi r^{2}](https://tex.z-dn.net/?f=%20SA%3D4%5Cpi%20r%5E%7B2%7D%20%20%20%20%20)