Answer:
It's be 60 because 30% of 60 is 18. Hope that helped :)
A helicopter starting on the ground is rising directly
into the air at a rate of 25 ft/sec. You are running on the
ground starting directly under the helicopter at a rate of 10
ft/sec. What is the rate at which the distance between you and the helicopter is changing when the helicopter has risen to a height of 60 ft in the air, assuming that, initially, it was 30 ft above you?
I want to understand how any why this is solved. So images/diagrams, detailed step by step breakdowns solutions are VERY much appreciated. Thanks!
Answer:
Oook, quick setup: pick a cartesian plane, be [tex](0;y(t))[/tex]the position of the helicopter as time passes, and [tex](x(t);0)[/tex] your position as you start running. In my horrible sketch, the green line is the distance when you start running, the red line is the distance you need, in general what you want is to move one end of the segment up, the other right, and stretch it.
That distance is easily found with the formula for the distance between two points in the plane, or [tex]d=\sqrt{(\Delta x)^2+(\Delta y)^2}= \sqrt{x^2(t)+y^2(t)}[/tex] (playing a bit with the squares). At this point we need to write down expressions for both [tex]x(t), y(t)[/tex] and find at what value of t we need to evaluate our distance.
For the sake of semplicity, let's start measuring times the moment you start running. Since speed is constant, both expressions will be of the form [tex]s=vt+s_0[/tex]
The equation for the runner becomes simply [tex]x(t)=10t[/tex], since you haven't moved until the heli is high enough.
The equation of the helicopter is [tex]y=25t+30[/tex] since the heli is 30ft above ground when you start running.
Finally, we need to know how many seconds have passed when the heli is at 60 ft above ground. that happens when [tex]60=25t+30 \rightarrow t=\frac{30}{25} = 1.20s[/tex]. in this time, you are at [tex]x(1.2)=10(1.2)=12ft[/tex] from the origin.
Plugging it in the distance formula you get: [tex]\sqrt{12^2+60^2}= \sqrt{144+3600}=4\sqrt {234}\approx 61.2ft[/tex]
y-5=2(x-3) slope intercept.
Answer:
y=2x-1
Step-by-step explanation:
Because this equation is in point-slope form and we need it in slope-intercept form, all we need to do is simplify y-5=2(x-3).
y-5=2x-6 Distribute.
+5 +5 Add 5 to both sides of the equation.
y=2x-1
Hope this helped! Have a great day ♥
How does the value of 2 dimes compare to the value of 2 dollars
Answer:
The 2 dollars has $1.80 more than the two dimes.
Step-by-step explanation:
2.00-0.20=1.80
3 2/3 + 2 3/5 + x = 8
Answer: x= [tex]-\frac {109}{15}[/tex]
What is the answer to this question?
Answer:
linear = 3x+y = 12, y = x/2 -3, y=x
nonlinear y = 6/x -2, y=3x³+5
2x+7y+7x=18
Find the value of Y
Answer:
y=−9/7x+18/7
Step-by-step explanation:
2x+7y+7x=18
9x+7y=18
Step 1: Add -9x to both sides.
9x+7y+−9x=18+−9x
7y=−9x+18
Step 2: Divide both sides by 7.
7y/7=−9x+18/7
y=−9/7x+18/7
Given :
2x + 7y + 7x = 18To Find :
The value of ySolution :
[tex]\qquad { \dashrightarrow \: { \sf{2x + 7y + 7x = 18}}}[/tex]
Adding the like terms :
[tex]\qquad { \dashrightarrow \: { \sf{ 7y + 9x = 18}}}[/tex]
Transposing 9y to the other side which then becomes negative :
[tex]\qquad { \dashrightarrow \: { \sf{ 7y = 18 - 9x}}}[/tex]
Dividing both sides by 7 :
[tex]\qquad { \dashrightarrow \: { \sf{ \dfrac{7y}{7} = \dfrac{18 - 9x}{7} }}}[/tex]
[tex]\qquad { \dashrightarrow \: { \sf{ y = \dfrac{18 - 9x}{7} }}}[/tex]
⠀
Therefore, the value of y = 18 – 9x/7 .
How many sides does the regular polygon have if each interior angle measure is four times the (1 point)
measure of each exterior angle measure?
Answer:
The exterior and interior angles must add up to 180 degrees. Thus, 180 divided by five gives the exterior angle as 36 degrees (and hence the interior angles as 144 degrees).
Answer:
10 Sides
Step-by-step explanation:
Int Angle + Ext Angle = 180
4Ext + Ext = 180
Ext = 36 degrees
-----
360/36 = 10 sides
Determine the slope from the given graph below:
The slope is−17
The slope is 5
The slope is 7
The slope is -5
Answer:
The slope is positive 7
Step-by-step explanation:
The y-intercept is -5, and the next point going upwards is positive 2. (Sorry I'm bad at explaining)
Answer:
The slope is 7
Step-by-step explanation:
(1,2)(0,-5)
[tex]m=\frac{-5-2}{0-1} ==\frac{-7}{-1} =7[/tex]
Hope this helps
How do we graph y+6=45(x+3)?
Answer:
.....,....................
In trapezoid DEFG, EG = 24.3 and DH = 9.4. Identify HF.
Answer:
HF = 14.9
Step-by-step explanation:
It is estimated that world reserves of oil currently stand at 2625
billion units. Oil is currently extracted at an annual rate of 45.5
billion units and this is set to increase by 2.6% a year. After how
many years will oil reserves run out
Answer:
35.4 years
Step-by-step explanation:
The annual consumption (in billions of units) is described by the exponential function ...
f(t) = 45.5·1.026^t
The accumulated consumption is described by the integral ...
[tex]\displaystyle\int_0^t{f(x)}\,dx=45.5\int_0^t{1.026^x}\,dx=45.5\left(\dfrac{1.026^t-1}{\ln{1.026}}\right)[/tex]
We want to find t such that the value of this integral is 2625, the estimated oil reserves.
2625 = 45.5/ln(1.026)·(1.026^t -1)
2625·ln(1.026)/45.5 +1 = 1.026^t ≈ 1.480832 +1 = 1.026^t
Taking natural logs, we have ...
ln(2.480832) = t·ln(1.026)
t ≈ ln(2.480832)/ln(1.026) ≈ 35.398
After about 35.4 years, the oil reserves will run out.
Figure B is a scale image of Figure A, as shown.
7
2.5
Figure A
Figure B
Enter the scale factor applied to Figure A to produce Figure B.
Enter your answer as a fraction, like this: 42/53
Explanation:
Divide the side length for B over the corresponding side length for A.
scale factor = B/A = 7/(2.5) = 2.8
Let's now convert this to a fraction
2.8 = 2 + 0.8 = 2 + 8/10 = 20/10 + 8/10 = (20+8)/10 = 28/10
Then reduce that fraction
28/10 = (14*2)/(5*2) = 14/5
Note that 14/5 = 2.8
Rewrite the quadratic function f(2) = 5x2 + 10x – 8 in standard form, f(x) = a (x – h)? + k, and give the vertex.
Answer: [tex]f(x) = 5(x+1)^{2} - 13[/tex]
Vertex = (-1, -13)
Step-by-step explanation:
[tex]f(x) = 5x^{2} + 10x - 8\\f(x) = 5(x^{2}+2x)-8\\f(x) = 5(x^{2}+2x+1-1)-8\\f(x) = 5((x+1)^{2}-1)-8\\f(x) = 5(x+1)^{2}-5-8\\f(x) = 5(x+1)^{2}-13[/tex]
Vertex = (h, k) = (-1, -13)
A rock is 7 feet below the surface of a river. If its position can be recorded as −7 feet, what would the position of 0 represent? (5 points)
Question 3 options:
1)
On the surface of the river
2)
At the bottom of the river
3)
7 feet above the surface of the river
4)
7 feet below the surface of the river
Answer:
A on the surface of the river
Step-by-step explanation:
100 persent correct
The approximate average distances from the sun to Mars and Mercury are listed
below:
Mars: 2.28 x 108 kilometers
Mercury: 5.79 x 107 kilometers
How many times farther from the sun is Mars? Write your answer in standard
notation, rounding to the nearest tenth.
Answer:
3.9
Step-by-step explanation:
Your calculator will tell you ...
(2.28×10^8)/(5.79×10^7) ≈ 3.9
Mars is about 3.9 times as far from the sun as Mercury.
The area
of this figure
is square inches.
20 in
28 in
30 in.
7 in
25 in.
Answer:
946 square Inches
Step-by-step explanation:
First, you should split up the shape into parts.
1st part 28x7
2nd part 30x25
We are multplying simply because
Area = Length x Width
Now that we have split up the parts lets multply them and add them togeher.
28 x 7 = 196
30 x 25 = 750
196 +750 = 946
So the area of this figure is 946 square inches.
Examine the figure. What is the measure of angle b?
Answer:
b =146
Step-by-step explanation:
34 and b form a straight line so they add to 180
b+34 = 180
b = 180-34
b =146
It takes cadence 36 hours to read 12 books. Write a unit rate that models the situation.
Answer:
three hours every 1 book
Step-by-step explanation:
36-12
6-2
3-1
Heheh... uhm, yeah, I don't do best with algebraic questions-
Answer:it's a for sure I think
Which of the following is equivalent to [picture]
A) a0 + a1 + a2 + a3 + a4 + a5
B) a1 + a2 + a3 + a4 + a5
C) a0 + a1 + a2 + . . .
D) a1 + a2 + a3 + . . . + a∞
Answer:
A) a0 + a1 + a2 + a3 + a4 + a5
Step-by-step explanation:
Answer:
A) a0 + a1 + a2 + a3 + a4 + a5
Step-by-step explanation:
Translate the sentence into an inequality.
Six times the sum of a number and 20 is greater than 16.
Use the variable c for the unknown number.
Answer:
6 (20 + c) > 16
Step-by-step explanation:
the sum of the number and 20 is 20 + c. so you multiply that equation by 6 giving you 6 (20 + c)
Round 523,009.974 to the nearest tenth
Answer:
Step-by-step explanation:
523,010.0
Which is equivalent to the following expression? (2x - 1)(x + 3)
Answer:
2x2+5x−3
Step-by-step explanation:
Expand the polynomial using the FOIL method.
Find an equation in the form y=ax^2+bx+c for the parabola passing through the points.
(3,25) (1,3) (-5,-15)
Thanks for the help! :)
Answer: [tex]x^2+7.0x-5.0x[/tex]
Step-by-step explanation:
solve systems of equations 6x+2y=1 y=-3x+3 using substition??? Need answers quickly!!!!!
8. A company makes electronic components for TV's. 95% pass final inspection (and 5% fail and need to be fixed). 120 components are inspected in one day. (10 points) b.What is the variance of the number that pass inspection in one day
Using the binomial distribution, it is found that the variance of the number that pass inspection in one day is 5.7.
For each component, there are only two possible outcomes, either it passes inspection, or it does not. The probability of a component passing inspections is independent of any other component, hence, the binomial distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x successes on n repeated trials, with p probability, and has variance given by:
[tex]V(X) = np(1 - p)[/tex]
In this problem:
95% pass final inspection, hence [tex]p = 0.95[/tex]120 components are inspected in one day, hence [tex]n = 120[/tex].The variance is given by:
[tex]V(X) = np(1 - p) = 120(0.95)(0.05) = 5.7[/tex]
The variance of the number that pass inspection in one day is 5.7.
To learn more about the binomial distribution, you can take a look at https://brainly.com/question/24863377
A rectangular garden is 24 feet wide. Its length is 4 feet more than twice the width. What is the area of the garden?
Answer:
1248
Step-by-step explanation:
w = 24feet
L=2w+4feet that means L= 2*24+4 =52
aera is 24*52=1248
What is the quotient of the following division problem?
71= 2 = ?
O A. 37 11
B. 35r1
O C. 35r2
O D. 34 r1
Answer:
35 remainder 1
Step-by-step explanation:
71 ÷ 2 = 35.5
The 35 is the whole number part of your answer. The .5 part of the answer is .5 of 2, which is 1
OR you can think that
35 × 2 =70. The 1 is the remaining part from 71.
(d) Given that the fifth and the seventh terms of the G.P form the first two consecutive terms of an arithmetic sequence, calculate the sum of the first 20 terms of the sequence
Step-by-step explanation:
the answer is shown in the photo
25. Solve for x:
4x-3/2=5/3
Answer:
X = 19/24
Step-by-step explanation:
Move the constant: 4x = 5/3 + 3/2
Add The Fractions: 5/3 + 3/2 = 19/6
Divide Both sides by 4: 4x/4 = 0. 19/6 ÷ 4 = 19/24