Answer:
x = 12
length = 4 cm
width = 20 cm
Step-by-step explanation:
a = lw
Plug in the givens
80 = (x - 8)(x + 8)
Multiply
80 = x^2 - 64
Add 64 to both sides
144 = x^2
Take the square root of both sides
x = ±12
(The negative root is extraneous since the dimensions can not be negative)
x = 12
length = x - 8 = 4 cm
width = x + 8 = 20 cm
I am honestly not sure about this answer... try Khan Academy. Or, try breaking it down into steps.
I hope this helped... sorry about that. I will try this concept soon. :)
You want to find the value of x for which the area under the curve to the left of x is 0.6. One way to do that is to create the cumulative distribution function (CDF) for the given PDF, then see where it is equal to 0.6.
Doing that, we find a = 5.
