Answer:
The answer is 21 minutes
Step-by-step explanation:
We use the equation Xf = Xo + vt
1) At 1:00 PM, child one leaves the starting point heading north at a constant velocity of 6 mi/hr or .1 [mi/min] (divide by 60 to convert from [mi/hr] to [mi/min])
2) He walks for 15 minutes before kid 2 starts walking. In 15 minutes he is able to cover 1.5 [mi]
3) Now, child 2 starts walking and we know that when the range reaches 3 miles, they won´t be able to communicate. So the sum of the final position of child 1 and child 2 must be 3[mi]
- Child 1 final position =>

- Child 2 final position =>

4) Sum the equations and equate to 3
5) Substitute the values we already know
6) in 15 + 6 minutes they will be 3miles apart
7) In 21 minutes they will still be able to communicate with one another.
Rotation about the origin
Answer:
26 rows
Step-by-step explanation:
this is like a rectangle length×width situation.
seats per row = s
number of rows = r
s × r = 884
s = r + 8
so, we can use e.g. the second equation in the first :
(r + 8) × r = 884
r² + 8r = 884
r² + 8r - 884 = 0
the general solution to such a quadratic equation is
x = (-b ± sqrt(b² - 4ac))/(2a)
in our case
x = r
a = 1
b = 8
c = -884
r = (-8 ± sqrt(8² - 4×1×-884))/(2×1) =
= (-8 ± sqrt(64 + 3536))/2 = (-8 ± sqrt(3600))/2 =
= (-8 ± 60)/2 = -4 ± 30
r1 = -4 + 30 = 26
r2 = -4 - 30 = -34
a negative number did not make any sense for the number of rows, so r = 26 is our answer.
Hypotenuse leg would be right
180-24=5
180-56=34
Both are equal
D