If x represents the width of the poster (including borders), the area of the finished poster can be written as
.. a = x*(390/(x -10) +8)
.. = 8x +390 +3900/(x -10)
Then the derivative with respect to x is
.. da/dx = 8 -3900/(x -10)^2
This is zero at the minimum area, where
.. x = √(3900/8) +10 ≈ 32.08 . . . . cm
The height is then
.. 390/(x -10) +8 = 8 +2√78 ≈ 25.66 . . . . cm
The poster with the smallest area is 32.08 cm wide by 25.66 cm tall.
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In these "border" problems, the smallest area will have the same overall dimension ratio that the borders have. Here, the poster is 10/8 = 1.25 times as wide as it is high.
1/2(2+a)=3a+4/3
first, you use the distributive property<span>
</span>then your problem changes to...
1 + 1/2a = 3a + 4/3
then you subtract 1/2a with 3a
1 = 2 1/2a +4/3
<span>
now you subtract 1 with 4/3
</span>
-1/3 = 2 1/2a
now you divide -1/3 with 2 1/2a
-2/15 = a
A = -2/15 is your answer. Hope this helps :)
Answer:
so its 50+.25(x) = y or 140. x is amount of minutes y is total
Answer:
x=7
Step-by-step explanation:
potato^3