Answer:
h(t) = -16t2 + 144
h(1) = -16(12) + 144 = 128 ft
h(2) = -16(22) + 144 = 80 ft
h(2) - h(1) = 80 - 128 = -48 ft
It fell 48 ft between t = 1 and t = 2 seconds.
It reaches the ground when h(t) = 0
0 = -16t2 + 144
t = √(144/16) s = 3s
It reaches the ground 3s after being dropped.
Step-by-step explanation:
Answer:
(3x+4)(5x+7)
Step-by-step explanation:
15x^2
+41x+28
Factor the expression by grouping. First, the expression needs to be rewritten as 15x^2
+ax+bx+28. To find a and b, set up a system to be solved.
a+b=41
ab=15×28=420
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 420.
1,420
2,210
3,140
4,105
5,84
6,70
7,60
10,42
12,35
14,30
15,28
20,21
Calculate the sum for each pair.
1+420=421
2+210=212
3+140=143
4+105=109
5+84=89
6+70=76
7+60=67
10+42=52
12+35=47
14+30=44
15+28=43
20+21=41
The solution is the pair that gives sum 41.
a=20
b=21
Rewrite 15x^2
+41x+28 as (15x^2
+20x)+(21x+28).
(15x^2
+20x)+(21x+28)
Factor out 5x in the first and 7 in the second group.
5x(3x+4)+7(3x+4)
Factor out common term 3x+4 by using distributive property.
(3x+4)(5x+7)
6^9 x 6^-7 = 6^2
x= -7
Hope this helps :)
Answer:
Step-by-step explanation:
This is <em>a separable differential equation</em>. Rearranging terms in the equation gives
Integration on both sides gives
where 
is a constant of integration.
The steps for solving the integral on the right hand side are presented below.
Therefore,
Multiply both sides by 
By taking exponents, we obtain
Isolate 
.
Since 
when 
, we obtain an initial condition 
.
We can use it to find the numeric value of the constant .
Substituting 
for and 
in the equation gives
Therefore, the solution of the given differential equation is
