Answer: (A) 6.6 sec (B) 6.89 sec
<u>Step-by-step explanation:</u>
y = -16t² + 1700
1000 = -16t² + 1700
<u>-1700</u> <u> -1700 </u>
-700 = -16t²
<u> ÷-16 </u> <u>÷-16 </u>
43.75 = t²
√43.75 = √t²
6.6 = t
***********************************
y = -16t² + 1700
940 = -16t² + 1700
<u>-1700</u> <u> -1700 </u>
-760 = -16t²
<u> ÷-16 </u> <u>÷-16 </u>
47.5 = t²
√47.5 = √t²
6.89 = t
Answer:
No solution
Step-by-step explanation:
We have

For the sum it is not correct to assume

Note that for

it is assumed
and in your case
for 
In fact, considering a set
we have
that satisfy 
This means that, by definition 
Therefore,

because the sum is empty.
For

we have other problems. Actually, this case is really bad.
Note that
has no value. In fact, if we consider for the case
, the cosine function oscillates between
, and therefore it is undefined. Thus, we cannot evaluate

and then

has no solution
His average speed for the first trip is 43 mph
Since Brian's average speed is x and he travels the first part for 215 miles in time t.
So, his distance d = xt
Also, the travels 75 more miles at a speed of 15 mph.
Since distance = speed time, the time he takes to cover this distance is
t' = distance/speed = 75 mi/15 mph = 5 hours
Since he covers both distances in the same time, we have that t = t' = 5 hours.
So, his average speed for the first trip x = d/t
= 215 mi/5 h
= 43 mph
His average speed for the first trip is 43 mph
Learn more about average speed here:
brainly.com/question/13605708
Answer:
Yes, it is possible to make a topless box with a volume of 6080 cm3 out of this cardboard sheet.
The dimensions of the cardboard sheet are 54 cm x 36 cm
Step-by-step explanation:
Let
x ----> the length of the cardboard sheet
y ----> the width of the cardboard sheet
we know that
----> equation A
The volume of the topless box is

where




substitute
----> equation B
substitute equation A in equation B
Solve for y
Solve the quadratic equation by graphing
The solution is y=36 cm
see the attached figure
Find the value of x
----> 
therefore
Yes, it is possible to make a topless box with a volume of 6080 cm3 out of this cardboard sheet.
The dimensions of the cardboard sheet are 54 cm x 36 cm