Deijah has $6.25.
Now, this 6.25 is comprised of 0.05s and 0.25s.
We know that there are 12 0.25s.
We now want to know how many remaining 0.05s there are.
Again, we know that the number of 0.05s he has, which is 12, multiplied by 0.05, plus the number of 0.25s he has, multiplied by 0.25, equals 6.25.
Thus, the answer is A, 0.25 x 12 + 0.05 x n = 6.25.
20/100 x 8000 = 1600
1600 x 3 = 4800
8000 - 4800 = 3200
The motorcycle is worth $3,200 after three years.
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.
2/3X
perpendicular slope is opposite of the sign and flip the fraction
