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4 years ago

QUICK!!! PLEASE HELP!!! 50 points.. and BRAINLIEST FOR THE QUICK AND CORRECT ANSWER.

Mathematics

1 answer:

faust18 [17]4 years ago

5 0

Answer: $e=-50|t-40|+2000$

The cable car’s elevation will be 750 feet after 15 minutes or 65 minutes.

Step-by-step explanation:

Given: A cable car begins its trip by moving up a hill. As it moves up, it gains elevation at a constant rate of 50 feet/minute until it reaches the peak at 2,000 feet.

Then, total time taken to reach the peak = (Distance) ÷ (speed)

= (2,000 feet) ÷ ( 50 feet/minute)

= 40 minutes

Then, as the car moves down to the hill’s base, its elevation drops at the same rate.

The equation that models the cable car’s elevation, e, after t minutes is

e= (constant rate)|t- time to reach peak |+ Peak's height

$e=-50|t-40|+2000$

When the cable car’s elevation will be 750 feet after minutes, then we have

$750=-50|t-40|+2000\\\\\Rightarrow\ -50|t-40|=750-2000\\\\\Rightarrow\ -50|t-40|=1250\\\\\Rightarrow|t-40|=-\dfrac{1250}{50}\\\\\Rightarrow|t-40|=-25\\\\\Rightarrow t-40=-25\text{ or }t-40=25\\\\\Rightarrow t=-25+40\text{ or }t=25+40\\\\\Rightarrow t=15\text{ or }t=65$

Time cannot be negative, so the cable car’s elevation will be 750 feet after 15 minutes or 65 minutes.

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4 years ago

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Step-by-step explanation:

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Where:

$\alpha_{1}$ , $\alpha_{2}$ , $\alpha_{3}$ - Scalar coefficients of linear combination, dimensionless.

By dividing each term by $\alpha_{3}$ :

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