Exemplo 5.81 de Prealgebra, 5.7 Simplify and Use Square Roots

Simplify and Use Square Roots: exemplo 5.81

Problema e solução em inglês, como no livro original.

After a car accident, the skid marks for one car measured $190$ feet. To the nearest tenth, what was the speed of the car (in mph) before the brakes were applied?

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An accident investigator measured the skid marks of a car and found their length was $76$ feet. To the nearest tenth, what was the speed of the car before the brakes were applied?

Como foi?

What are you asked to find?	The speed of the car before the brakes were applied
Write a phrase.	The speed of the car
Translate to an expression.	$\sqrt{24 d}$
Evaluate $\sqrt{24 d}$ when $d = 190 .$	$\sqrt{24 \cdot 190}$
Multiply.	$\sqrt{4,560}$
Use your calculator.	$67.527772 ...$
Round to tenths.	$67.5$
Write a sentence.	The speed of the car was approximately 67.5 miles per hour.

What are you asked to find?	The speed of the car before the brakes were applied
Write a phrase.	The speed of the car
Translate to an expression.	$\sqrt{24 d}$
Evaluate $\sqrt{24 d}$ when $d = 190 .$	$\sqrt{24 \cdot 190}$
Multiply.	$\sqrt{4,560}$
Use your calculator.	$67.527772 ...$
Round to tenths.	$67.5$
Write a sentence.	The speed of the car was approximately 67.5 miles per hour.

Simplify and Use Square Roots: exemplo 5.81

Solução

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Simplify and Use Square Roots: exemplo 5.81

Solução

Sua vez