Its the middle two. Hope I helped
H(t) = Ho +Vot - gt^2/2
Vo = 19.6 m/s
Ho = 58.8 m
g = 9.8 m/s^2
H(t) = 58.8 + 19.6t -9.8t^2/2 = 58.8 + 19.6t - 4.9t^2
Maximun height is at the vertex of the parabole
To find the vertex, first find the roots.
58.8 + 19.6t - 4.9t^2 = 0
Divide by 4.9
12 + 4t - t^2 = 0
Change sign and reorder
t^2 - 4t -12 = 0
Factor
(t - 6)(t + 2) =0 ==> t = 6 and t = -2.
The vertex is in the mid point between both roots
Find H(t) for: t = [6 - 2]/2 =4/2 = 2
Find H(t) for t = 2
H(6) = 58.8 + 19.6(2) - 4.9(2)^2 = 78.4
Answer: the maximum height is 78.4 m
B = ym + y
B - y = ym
(B - y) / y = m
or
B/y - 1 = m
Answer:
1.5 seconds
Step-by-step explanation:
h=-16t² – 16t+ 60
When the rock enter the water, the height is 0. ... h=0
0 = -16t² – 16t+ 60 = -4 * (4t² - 4t +15) = -4* (2t - 3) (2t +5)
2t-3=0 or 2t+5 = 0
t = 3/2 or t = -5/2 (time can't be negative)
t = 3/2 or 1.5
Answer:
The polygon has 9 sides
Step-by-step explanation:
we know that
A regular polygon has equal length sides and equal interior angles
step 1
Find the measure of the interior angle
Remember that
The interior angle plus the exterior angle must be equal to 180 degrees (form a linear pair)
Let
x ----> the measure of each interior angle in the regular polygon
so

solve for x

step 2
Find the number of sides of the regular polygon
we know that
The measure of each interior angle in a regular polygon is given by the formula

where
n is the number of sides of the polygon
substitute the given values

solve for n

therefore
The polygon has 9 sides