The braking distance, D, of a car is directly proportional to the square of its speed, v. When d=5, v=10

Mathematics

1 answer:

elena-s [515]3 years ago

3 0

$d \propto v^2$

$\implies d=kv^2$

substitute the given values, $5=k(10)^2\implies k=\frac1{20}$

now, $d=\frac{1}{20}\times( 70)^2=\frac{70\times70}{20}=245$

A big blunder from my side, now fixed!

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FromTheMoon [43]

Answer:

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Step-by-step explanation:

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Ksenya-84 [330]

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Multiplying equation 1 by three and subtracting equation 2 from it, we get:

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3 years ago

I’m confused nd stuck

andreev551 [17]

Answer:

B. (4,2)

Step-by-step explanation:

The answer is where the lines intersect.

Hope this helps!

If not, I am sorry.

6 0

2 years ago