The error.....Kelvin just figured the 60% markdown cost...not the final price
the final price would be : 30.65 - 0.60(30.65) = 30.65 - 18.39 = 12.26
so 12.26 is the final price
or another way to do this is : if it is marked down 60%, then u r actually paying 40%......0.40(30.65) = 12.26
Since the parabola passes by the center its equation is:
y = ax². But it opens downward, that means the coefficient a is negative.
Then the equation becomes:
y = - ax², with x = 0 as its axis of symmetry.
We are given that the height is 84 ft when the opening downward is 42 ft.
That means to the (height) y, corresponds x =+21 & x=-21 (due to symmetry).
In order to calculate a let's plug y & x with their related values:
y = - ax²
84 = - a(21)²
84 = - a(441) and a = - 84/441 ↔ a = - 4/21
And the final equation is : y = -4/21. x²
Answer:
It will take Lin an hour and 25 minutes at her constant speed, and it will take Jada at her constant speed an hour and 30 minutes.
SO, Lin will arrive at 4:25
and Jada will arrive at 4:30
There is a 5 minute difference in time.
Step-by-step explanation:
From the facts given, Lin can walk 13 miles in 5 hours which when you divide means she can walk 2.6 mph (miles per hour), and Jada can walk 2.5 mph.
To get these answers you divide the current speeds into the total distance
For example, in Lin's case...
3.25 (The 3 and 1/4 mile converted to decimal form)
2.6 (Lin's Average speed per hour)
3.25/2.6=1.25
1.25 (1 hour and 25 minutes)
= (1/2) (17.2) (7.1) sin (21.67)
= 22.5470 square meters
