Answer:
140 minutes
Step-by-step explanation:
After 28 mins you've gone 4 miles, assuming this rate is constant and you dont slow down or speed up, in order to get to 20 miles you will have run 5x as much (20/4 = 5), thus 5x the amount of time (28x5).
20/4 = 5
5x28 = 140
3x + 1 = (x-1)^2
3x + 1 = x^2 - 2x + 1
0 = x^2 -5x
0 = x(x-5)
x = 0,5
Hope this helps!
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volume of the center sphere = 4/3*PI*r^3
r = 3 ( given in the picture)
so 4/3 * 3.14 *3^3 = 113.04 cubic feet
volume of 1 cone: pi *r^2 *h/3
r = 3 and h=3 ( given in the picture)
so 3.14 * 3^2 * 3/3 = 28.26 cubic feet
there are 4 cones so 28.26* 4 = 113.04 cubic feet
113.04 + 113.04 = 226.08 cubic feet
rounded to nearest cubic foot = 226 cubic feet
A.) f(x) = x^2 because 2 > 1. So f(2) = 4.
A is correct.
B.) f(x) = x^2 because 5 > 1. So f(5) = 25.
B is incorrect.
C.) f(x) = 2x because -2 < 1. So f(-2) = -4.
C is incorrect.
D.) f(x) = 5 because x = 1.
D is correct.
So the answer is A and D.