F(X) = 6/X
F(X) = 6 • 1/X
F(X) = 6 • x^-1
F(X) = 6x^-1
F'(X) = 6 • d(x^-1)/dx
F'(X) = 6 • -1x^-1-1
F'(X) = 6 • -1x^-2
F'(X) = -6x^-2
F'(X) = -6/x^2
F'(-2) = -6/(-2)^2
F'(-2) = -6/4
F'(-2) = -3/2
The solution would be C. -3/2.
80=-8a
We are trying to solve for a. So we need to get a alone. To do that we have to divide each side by -8.
80/-8= -8a/-8
Once you have solved each side you will get the following.
-10=a
Morgan should first take the 40% off then apply the $15 coupon
Lets say her total was $150.
If you take the 40% off first, you get $90
150 * .6 = 90 (since you are taking off 40% you are still paying the rest of the 60% so you can just save extra steps by multiplying by .6 and not .4)
Now you subtract 15 from that value.
90 - 15 = 75 If Morgan takes the 40% off first and then applies the $15 dollar coupon, she has to pay $75.
If she applies the $15 coupon first, her total before the 40% is $135
150 - 15 = 135
The total will come out to be $81
$135 * .6 = 81
If Morgan takes the discount first before applying the coupon she has to pay less and saves the most money.
