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Solve quadratic equations: word problems

Lillian enjoys looking at maps. Last weekend, she looked at a map that showed the elevation of the highest cities in the world, all of which are at least

4,500

meters above sea level. Of the

16

cities on the list,

11

are in Asia and the other

5

are in South America. The median elevation of the cities is

4,727.5

meters above sea level, and the interquartile range is

305

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Which is a measure of how much the cities' elevations vary?

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11

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305

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4,500

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4,727.5

Write the equation

2(x+3)=2x+6

as a system of equations.

After learning how to fly, Wendy reduced her daily commute time by

75\%

. Previously, her commute took

m

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Which of the following expressions could represent Wendy's commute time, in minutes, after she learned how to fly?

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2

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1.75m

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0.75m

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(3)/(4)m

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(1)/(4)m

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0.25m

Ms. Kent writes the two functions shown in the box on the whiteboard and asks her students to solve the system.

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\begin{array}{l}f(x)=0.25(0.5)^{x} \\ g(x)=(2)^{x}\end{array}

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Which is the solution to this system?

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x=-1

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x=0

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x=0.5

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x=1

A pharmaceutical company is testing a new dug designed to reduce blood pressure. The current standard medication has on average reduction of

15

points in systolic blood pressure. The compony believes that their new drug is more effective in reducing blood pressure. They conduct a study when they administer the new drug to a random sample of

50

patents and find that the average reduction in systolic blood pressure is

18

points with a standard deviation of

5

points. lest the hypothesis that the average than

15

points, using a significance level of

0.01

h(t) = -16t^{2} + 144

represents the height,

h(t)

, in feet, of an object from the ground at

t

seconds after it is dropped. A realistic domain (for time) for this function is:

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(A)

-3 \leq t \leq 3

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(B)

0 \leq t \leq 3

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(C)

0 \leq h \leq 144

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(D)

all real numbers