Answer:
13 ft/s
Step-by-step explanation:
t seconds after the boy passes under the balloon the distance between them is ...
d = √((15t)² +(45+5t)²) = √(250t² +450t +2025)
The rate of change of d with respect to t is ...
dd/dt = (500t +450)/(2√(250t² +450t +2025)) = (50t +45)/√(10t² +18t +81)
At t=3, this derivative evaluates to ...
dd/dt = (50·3 +45)/√(90+54+81) = 195/15 = 13
The distance between the boy and the balloon is increasing at the rate of 13 ft per second.
_____
The boy is moving horizontally at 15 ft/s, so his position relative to the spot under the balloon is 15t feet after t seconds.
The balloon starts at 45 feet above the boy and is moving upward at 5 ft/s, so its vertical distance from the spot under the balloon is 45+5t feet after t seconds.
The straight-line distance between the boy and the balloon is found as the hypotenuse of a right triangle with legs 15t and (45+5t). Using the Pythagorean theorem, that distance is ...
d = √((15t)² + (45+5t)²)
Answer:
$936.94
Step-by-step explanation:
Remember, that because you paid $2,175 up front (down payment), you can borrow $2,175 less from the bank to purchase the car. So first step: Take new car price of $19,725.00 and multiply it by the sales tax percentage ($19,725 * 0.0475) to get $936.94 of tax.
Factor 4
4=1 times 4
2 times 2
they don't add to 2
set up equation
x+y=2
xy=4
first equation, subtract x from both sides
y=2-x
subsitute for y
x(2-x)=4
distribute
2x-x^2=4
add x^2
2x=x^2+4
subtract 2x
0=x^2-2x+4
use quadratic formula which is
if you have ax^2+bx+c=0 then
x=
so
1x^2-2x+4=0
a=1
b=-2
c=4
x=
x=
x=
we have
and that doesn't give a real solution
therefor there are no real solutions
but if you want to solve fully
x=
i=
x=
x=
x=
or x=
(those are the 2 numbers)
Answer:
C
Step-by-step explanation:
Answer:
a) The percentage of athletes whose GPA more than 1.665 is 87.49%.
b) John's GPA is 3.645.
Step-by-step explanation:
In a set with mean and standard deviation , the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
a)Find the percentage of athletes whose GPA more than 1.665.
This is 1 subtracted by the pvalue of Z when X = 1.665. So
has a pvalue of 0.1251
1 - 0.1251 = 0.8749
The percentage of athletes whose GPA more than 1.665 is 87.49%.
b) John's GPA is more than 85.31 percent of the athletes in the study. Compute his GPA.
His GPA is X when Z has a pvalue of 0.8531. So it is X when Z = 1.05.
John's GPA is 3.645.