C(x) = 400 + 20x - 0.2x²
c(30) = 400 + 20(30) - 0.2(30)²
= 400 + 600 - 0.2(900)
= 1000 - 180
= 820
It costs $820 when 30 radios are produced.
Marginal cost is how much it would cost to make one MORE of the same product so now we find how much it costs to produce 31 radios and compare the two.
c(31) = 400 + 20(31) - 0.2(31)²
= 400 + 620 - 0.2(961)
= 1020 - 192.2
= 827.8 or ≈828.
Now we find the difference which means we subtract the two.
828 - 820 = 8.
Your marginal cost is $8.
To compare we can also do 29 radios.
c(29) = 400 + 20(29) - 0.2(29)² = 811.8 or ≈812
820 - 812 = 8.
The distance formula is shown here. If you plug your coordinates into the formula, you will get d=square root of (5-3)^2+(8-10)^2 which equals 2.828
Answer:
-4r²-3s²
Step-by-step explanation:
Remove unnecessary parentheses:
r²+s²-(5r²+4s²)
Connect like terms:
-4r²+s²-4s²
Simplify/ collect like terms:
-4r²-3s²
Solution:
-4r²-3s²
Answer:

Step-by-step explanation:
We need to note that this is an equation, in which we can solve for x.

We can use a calculator to find the tangent of 39 - we type 39 into the calculator then press the "TAN" button to find it's tangent. We find that to be around 0.81.
We now have the formula simplified down to
. To solve for x, we want to isolate it on one side, so we can multiply both sides by 68 to get rid of the fraction.
We know have 
, so x is approximately 55.
Hope this helped!