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.
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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)
85 = 10x+15
70 = 10x
x = 7
180-85 = 95 = z
So u turn the percent into a decimal.
0.10
Now multiply 1200 * 0.10
1200*0.10= 120 ( 120 is the amount that is gonna increase)
So if it says 5 years, than your gonna multiply 120 * 5
120*5 =600
So your gonna add 600 to 1200.
So in five years your gonna be making 1,800.
An easier way would be to use prt
Principle * rate * time
1200 * 0.10* 5
= 600
So now you just add 600 to 1200
= 1800
Answer:
D. –5.2 + (–6.4) = –11.6
Step-by-step explanation:
First, you can eliminate A and C because 5.2 is positive. Since the red arrow is pointing left, it indicates that the number (-5.2) is negative.
Then, you look at the second arrow, the green one. It is pointing left, so it would be -6.4.
I hope this helps :)
