Well, the first 16 were about 16*75=$1200 extra. The last 8 were $720 lost. Thus, the total profit is $480. He bought them with $7200, which means the profit is around 6.67%.
So sorry fir it being this late but the answer is B
25x² + 1 = 5
25x² + 1 - 5 = 0
25x² - 4 = 0 By difference of two squares
(5x)² - (2)² = 0
(5x - 2)(5x + 2) = 0
5x - 2 = 0 or 5x + 2 = 0
5x = 0 + 2 5x = 0 - 2
5x = 2 5x = -2
x = 2/5 x = -2/5
x = 0.4 x = -0.4
x = + 0.4 or -0.4
With a given parallel line and a given point on the line
we can use the point-line method: y-y0=m(x-x0)
where
y=mx+k is the given line, and
(x0,y0) is the given point.
Here
m=-10, k=-5, (x0,y0)=(-3,5)
=> the required line L is given by:
L: y-5=-10(x-(-3))
on simplification
L: y=-10x-30+5
L: y=-10x-25