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3 years ago

9

Two trains leave the same station at the same time, but are headed in opposite directions. One train travels at 70 mph and the o

ther train travels at 80 mph.
How much times passes until the trains are 600 mi apart?

Enter your answer in the box

___hours

2 answers:

uranmaximum [27]3 years ago

4 0

Let

x--------> the time in hours

y-------> the distance in miles

we know that

The speed is equal to

$Speed=\frac{distance}{time}$

in this problem

$Speed=\frac{y}{x}$

$y=(Speed)*x$

<u>Equation First Train</u>

$y1=70x$

<u>Equation Second Train</u>

$y2=80x$

$y1+y2=600\ miles$ ---------> equation $1$

Substitute the values of $y1$ and $y2$ in the equation $1$

$70x+80x=600$

Solve for x

$150x=600$

$x=4\ hours$

therefore

<u>the answer is</u>

$4\ hours$

Xelga [282]3 years ago

4 0

4 hours til the trains are 600 miles apart

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NISA [10]

The least (or lowest) common denominator of 3, 16 and 8 is 16. That already points us to answer A.

Checking for each fraction:

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ivanzaharov [21]

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3 years ago

Fill in the blank for Remainder Therom<br><br><br> x 3 + x 2 - 21x - 45 = (x + 3)(x - 5)(x+?)

icang [17]

Not sure about remainder theorem but I'm sure that the last terms should all multiply tho the last term

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3 years ago

Read 2 more answers

the distance around tims rectangulr book is 48 centimeters the length of each longer side is 14 cm what is the length of each sh

yanalaym [24]

let the length of each shorter side be x

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3 years ago

Convert the Cartesian equation (x 2 + y 2)2 = 4(x 2 - y 2) to a polar equation.

SashulF [63]

<u>ANSWER</u>

${r}^{2} = 4 \cos2\theta$

<u>EXPLANATION</u>

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${( {x}^{2} + {y}^{2} )}^{2} = 4( {x}^{2} - {y}^{2} )$

We substitute

$x = r \cos( \theta)$

$y = r \sin( \theta)$

and

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This implies that

${( {r}^{2} )}^{2} = 4(( { r \cos\theta) }^{2} - {(r \sin\theta) }^{2} )$

Let us evaluate the exponents to get:

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Factor the RHS to get:

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Divide through by r²

${r}^{2} = 4 ({ \cos^{2}\theta } - \sin^{2}\theta)$

Apply the double angle identity

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The polar equation then becomes:

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7 0

3 years ago