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2 years ago

The speed of a sparrow is x km/h in still air. When the

Mathematics

1 answer:

Semmy [17]2 years ago

4 0

Answer:

x = 5m/s

Step-by-step explanation:

Distance flying out = 12 km (headwind)

Distance flying back = 12 km (tailwind)

total distance = 12 + 12 =24 km

wind speed = 1km/h

speed going out (with headwind) = (x - 1) km/h

speed coming back (with tailwind) = (x + 1) km/h

Time taken to go out = distance going out / speed going out

= 12 / (x-1)

Time taken to come back = distance coming back / speed coming back

= 12 / (x+1)

total time = time taken to go out + time taken to come back

5 =[ 12/(x-1) ] + [ 12/(x-1)]

expanding this, we will get

5x² - 24x - 5 = 0

solving quadratic equation, we will get

x = -1/5 (impossible because speed cannot be negative)

x = 5 (answer)

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A gym charges a $20 sign-up fee plus $25 per month. You have a $120 gift card for the gym. When does the total spent on your gym

kati45 [8]

After 4 months! You do 120-20=100 which indicates only the month prices, then 100 divided by 25 which is 4!

7 0

2 years ago

A magazine advertises that a subscription price if $29.99(for12 issues) represents a savings of 70% from the newsstand price.Wha

Ede4ka [16]

$29.99 is the final price.
"y" is the original price.
Subtract the savings from the original price to get the final price of $29.99.
70% = 70/100 = .70
y - (y x .70) = 29.99
y - .7y = 29.99
.3y = 29.99
.3y/.3 = 29.99/.3
y = 99.96667
y = $99.97 (rounded)

7 0

1 year ago

Read 2 more answers

Solve the following problem: An investor earned triple the profits of what she earned last year. If she made $500,000.48 total f

myrzilka [38]

Answer:

$125,000.12 last year

$375,000.36 this year

Step-by-step explanation:

Last year, her profits were x.

This year, the profits are three times greater, so they are 3x.

Altogether for both years, the profits are x + 3x = 4x.

The profits for both years combined are $500,000.48

4x = 500,000.48

Divide both sides by 4.

x = 500,000.48/4

x = 125,000.12

The profits last year were $125,000.12

This year, the profits were 3x = 3(125,000.12) = 375,000.36, or $375,000.36

7 0

1 year ago

_____ are ______ midsegments of ΔWXY.

iVinArrow [24]

Answer:

The perimeter of Δ WXY is 14.50 cm ⇒ the last answer

Step-by-step explanation:

* Lets explain how to solve the problem

- There is a fact in any triangle; the segment joining the midpoints of

two side of a triangle is parallel to the 3rd side and half its length

* Lets use this fact to solve the problem

- In Δ WXY

∵ Q is the midpoint of WX

∵ R is the midpoint of XY

∵ S is the midpoint of YW

- By using the fact above

∴ QR = 1/2 WY

∴ RS = 1/2 WX

∴ SQ = 1/2 XY

- Lets calculate the length of the sides of Δ WXY

∵ QR = 1/2 WY

∵ QR = 2.93

∴ 2.93 = 1/2 WY ⇒ multiply both sides by 2

∴ WY = 5.86 cm

∵ RS = 1/2 WX

∵ RS = 2.04

∴ 2.04 = 1/2 WX ⇒ multiply both sides by 2

∴ WX = 4.08 cm

∵ SQ = 1/2 XY

∵ SQ = 2.28

∴ 2.28 = 1/2 XY ⇒ multiply both sides by 2

∴ XY = 4.56 cm

- Lets find the perimeter of Δ WXY

∵ The perimeter of Δ WXY = WX + XY + YW

∴ The perimeter of Δ WXY = 5.86 + 4.08 + 4.56 = 14.50

* The perimeter of Δ WXY is 14.50 cm

3 0

2 years ago

Read 2 more answers

Complete the equation of the line through ( 2 , 1 ) (2,1)left parenthesis, 2, comma, 1, right parenthesis and ( 5 8 ) (5,−8)left

Assoli18 [71]

Answer:

y = -3m + 7

Step-by-step explanation:

Given the two point:

A (2, 1)
B (5, -8)

We use Slope-Intercept Form to create the equation of the line that goes through the two points above

y =mx + b where m is the slope and b is the y-intercept

Step 1: find the slope of it

$m=\frac{y_2-y_1}{x_2-x_1}$

<=> m = $\frac{-8-1}{5-2} = \frac{-9}{3} = -3$

=> our equation: y = -3x + b (1)

Now, plug one of the points (either one!) together with m into (1), we have:

1 = -3*2+ b

<=> b = 7

Hence, the equation is: y = -3m + 7

Hope it will find you well.

3 0

1 year ago