F(x) = 18-x^2 is a parabola having vertex at (0, 18) and opening downwards.
g(x) = 2x^2-9 is a parabola having vertex at (0, -9) and opening upwards.
By symmetry, let the x-coordinates of the vertices of rectangle be x and -x => its width is 2x.
Height of the rectangle is y1 + y2, where y1 is the y-coordinate of the vertex on the parabola f and y2 is that of g.
=> Area, A
= 2x (y1 - y2)
= 2x (18 - x^2 - 2x^2 + 9)
= 2x (27 - 3x^2)
= 54x - 6x^3
For area to be maximum, dA/dx = 0 and d²A/dx² < 0
=> 54 - 18x^2 = 0
=> x = √3 (note: x = - √3 gives the x-coordinate of vertex in second and third quadrants)
d²A/dx² = - 36x < 0 for x = √3
=> maximum area
= 54(√3) - 6(√3)^3
= 54√3 - 18√3
= 36√3.
Answer:
5)1075000000
6)333.333333333
Step-by-step explanation:
5)4.3*10^3=4300
2.5*10^5=250000
6)3*10^6=3000000
9*10^3=9000
90 = 30+10+3x
This equation shows that all the prices of the the bag, eraser, and pencils equals $90. So now all we have to do to find the price of a pencil is solve the equation.
First add the 30 and 10 together.
90 = 40+3x
Then subtract 40 from each side
50 = 3x
Lastly divide each side by 3
x = 16.67
The price per pencil is $16.67
Hope this helps!
Answer:
the monthly payment would be $86.00
Step-by-step explanation:
