Answer:
a) 8 seconds
b) 3 seconds
c) 170 meters
Step-by-step explanation:
a) When the ball lands in the sea, s = -80.
-80 = 30t − 5t²
5t² − 30t − 80 = 0
t² − 6t − 16 = 0
(t + 2) (t − 8) = 0
t = -2 or 8
t = 8 seconds
b) The ball reaches its highest point when the velocity is 0 (or at the vertex of the parabola).
t = -b / (2a)
t = -30 / (2 × -5)
t = 3 seconds
c) The highest point is:
s = 30(3) − 5(3)²
s = 45
So the ball rises 45 meters, falls 45 meters, then falls 80 meters.
The total distance traveled is 45 + 45 + 80 = 170 meters.
Answer:
A system has infinitely many solutions when it is consistent and the number of variables is more than the number of nonzero rows in the rref of the matrix. For example if the rref is ��has solution set (4-3z, 5+2z, z) where z can be any real number.
The price p based on the equation given is p = 3000 - 0.1x.
<h3>How to express the price?</h3>
The equation given in the question is x = 3000 - 10p. The price(p) will be:
x = 3000 - 10p.
Make p the subject of the formula
x + 10p = 3000
10p = 3000 - x
p = (3000 - x)/10
p = 3000 - 0.1x
The revenue will be price multiplied by quantity. This will be:
= (3000 - 0.1x) × x
= 3000x - 0.1x²
The marginal revenue will be calculated after differentiating. This will be:
= 3000x - 0.1x²
= 3000 - 0.2x
The demand which is the quantity based on the information will be:
3000 - 0.2x = 0
0.2x = 3000
x = 1500
Learn more about demand on:
brainly.com/question/1245771
#SPJ1
Answer:
20mph
Step-by-step explanation:
because when you divide the 280 it goes by 20 mph to get to 280 miles by quarters but in 20s