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3 years ago

Find two positive numbers such that the sum of the first and twice the second is 88

Mathematics

1 answer:

Juli2301 [7.4K]3 years ago

7 0

the 2 numbers are 8 and 40

40*2 = 80 +8 = 88

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This is a 3 part 1 question each part on how to locate the plane and a small explanation report working out the recovery details

sesenic [268]

Third leg.

The crew flies at a speed of 560 mi/h in direction N-20°-E.

The wind has a speed of 35 mi/h and a direction S-10°-E.

We then can draw this as:

We have to add the two vectors to find the actual speed and direction.

We will start by adding the x-coordinate (W-E axis):

$\begin{gathered} x=560\cdot\sin (20\degree)+35\cdot\sin (10\degree) \\ x\approx560\cdot0.342+35\cdot0.174 \\ x\approx191.53+6.08 \\ x\approx197.61 \end{gathered}$

and the y-coordinate (S-N axis) is:

$\begin{gathered} y=560\cdot\cos (20\degree)-35\cdot\cos (10\degree) \\ y\approx560\cdot0.940-35\cdot0.985 \\ y\approx526.23-34.47 \\ y\approx491.76 \end{gathered}$

Then, the actual speed vector is v3=(197.61, 491.76).

The starting location for the third leg is R2=(216.66, 167.67) [taken from the previous answer].

Then, we have to calculate the displacement in 20 minutes using the actual speed vector.

We can calculate the movement in each of the axis. For the x-axis:

$\begin{gathered} R_{3x}=R_{2x}+v_{3x}\cdot t \\ R_{3x}=216.66+197.61\cdot\frac{1}{3} \\ R_{3x}=216.66+65.87 \\ R_{3x}=282.53 \end{gathered}$

NOTE: 20 minutes represents 1/3 of an hour.

We can do the same with the y-coordinate:

$\begin{gathered} R_{3y}=R_{2y}+v_{3y}\cdot t \\ R_{3y}=167.67+491.76\cdot\frac{1}{3} \\ R_{3y}=167.67+163.92 \\ R_{3y}=331.59 \end{gathered}$

The final position is R3 = (282.53, 331.59).

To find the distance from the origin and direction, we transform the cartesian coordinates of R3 into polar coordinates:

The distance can be calculated as if it was a right triangle:

$\begin{gathered} d^2=x^2+y^2_{} \\ d^2=282.53^2+331.59^2 \\ d^2=79823.20+109951.93 \\ d^2=189775.13 \\ d=\sqrt[]{189775.13} \\ d\approx435.63 \end{gathered}$

The angle, from E to N, can be calculated as:

$\begin{gathered} \tan (\alpha)=\frac{y}{x} \\ \tan (\alpha)=\frac{331.59}{282.53} \\ \tan (\alpha)\approx1.1736 \\ \alpha=\arctan (1.1736) \\ \alpha=49.56\degree \end{gathered}$

If we want to express it from N to E, we substract the angle from 90°:

$\beta=90\degree-\alpha=90-49.56=40.44\degree$

Answer: the final location can be represented with the vector (282.53, 331.59).

1) The distance from the origin is 435.63 miles and

2) the direction is N-40°-E.

7 0

1 year ago

Find the area of the shaded region

o-na [289]

so hmmm let's get the area of the whole hexagon, and then get the area of the circle inside it, then <u>subtract the area of the circle from that of the hexagon's</u>, what's leftover is what we didn't subtract, namely the shaded part.

$\textit{area of a regular polygon}\\\\ A=\cfrac{1}{4}ns^2\cot\stackrel{\stackrel{degrees}{\downarrow }}{\left( \frac{180}{n} \right)}~ \begin{cases} n=\textit{number of sides}\\ s=\textit{length of a side}\\[-0.5em] \hrulefill\\ n=\stackrel{hexagon}{6}\\ s=\frac{9}{2} \end{cases}\implies A=\cfrac{1}{4}(6)\left( \cfrac{9}{2} \right)^2 \cot\left( \cfrac{180}{6} \right)$

$A=\cfrac{1}{4}(6)\cfrac{9^2}{2^2} \cot(30^o)\implies A=\cfrac{243}{8}\cot(30^o)\implies A=\cfrac{243\sqrt{3}}{8} \\\\[-0.35em] ~\dotfill\\\\ \textit{area of circle}\\\\ A=\pi r^2~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=\frac{4}{5} \end{cases}\implies A=\pi \left( \cfrac{4}{5} \right)^2\implies A=\cfrac{16\pi }{25} \\\\[-0.35em] ~\dotfill$

$\stackrel{\textit{area of the hexagon}}{\cfrac{243\sqrt{3}}{8}}~~ - ~~\stackrel{\textit{area of the circle}}{\cfrac{16\pi }{25}}\implies \cfrac{6075\sqrt{3}-128\pi }{200}$

5 0

2 years ago

A right triangle ABC is shown. Leg AC has length 18, leg BC has length 24, and hypotenuse AB has length 30. Find the exact value

Tresset [83]

Although there i no triangle given as the question requires, I am still going to answer because I understand it.

ABC is a right angled triangle. The triangle is 90° at C.

The trigonometric ratio sine is given by, sine = opposite/hypotenuse .
Cosine = adjacent/hypotenuse

So therefore, Sin A = 24/30
= 4/5

Cos A = 18/30
= 3/5

8 0

3 years ago

Read 2 more answers

1) Sally sprints 300 yards in a minute. Quadra runs 20% further than Sally in the same time.

Free_Kalibri [48]

1) answer = 360
explanation =
-> 10% of 300 = 300*10
-> 10% of 300 = 30
-> 20% = 10% x 2
-> 20% = 30 x 2
-> 20% = 60
-> 300 yards ( distance they ran ) + 60 yards ( how much more distance Quadra ran ) = 360 yards
2) answer = Newton spends 10 minutes or 1/6 hours reading
explanation =
-> 25% = 1/4
-> 40*4= 10
-> 1 hrs = 60 min
-> 10 min x 6 = 60 min
-> 1/6 hrs = 10 min
3) answer = 30 fish
explanation =
-> 40% = 12
-> 10% = 3
-> 40*4=10 and 12*4=3
-> 10% + 40% = 50% so 12 + 3 = 15
-> 50% = 15 and 100% = 15 x 2
-> 100% = 30
4) answer = 30
explanation =
-> 1/4 is equal to 25 %
-> add up all the prrcentages ( 25% + 10% + 15% = 50% )
-> she have 50% of tej chocolates Which were in the tin she bought away and kept 15 chocolates to herself
-> 50% = 1/2
-> 50% x 2 = 100%
-> 15 x 2 = 30

3 0

2 years ago

What is the y-intercept for the graph of 7x – 3y = –5?

AysviL [449]

2 ways to find the y int.

(1) put the equation in y = mx + b form and the y int will be in the b position
7x - 3y = -5
-3y = -7x - 5
y = 7/3x + 5/3....so 5/3 is ur y int

(2) another way is to sub in 0 for x and solve for y
7(0) - 3y = -5
-3y = -5
y = -5/-3
y = 5/3...ur y int

3 0

3 years ago

Read 2 more answers