Brad M. answered • 10/05/13

Lines, Parabolas, Cubics, Polynomials, Sine Waves, and Exp-Log Curves

**Five days**of $1.25 = $6.25 ... Best wishes, ma'am :)

Sara A.

asked • 10/05/13charges a fee of $31.75 plus $4.00 per day to rent the same car. Use a graphing calculator, find the number of days for which the costs are the same. Round your answer to the nearest whole day.

Can someone solve this and explain how?

And also these,

3. {y=-x-9

{3x-y=-11

4. {-0.2x-0.8y=0

{0.7x-0.1y=-2.9

5 {-2x+3y+4=0

{6x-9y=-2

Without graphing, classify each system as independent, dependent, or inconsistent.

{-x-y=-2

{3x-3y=6

{y=2x-7

{4x-2y=14

{8x+2y=0

{y=-4x+2

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Brad M. answered • 10/05/13

Tutor

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Lines, Parabolas, Cubics, Polynomials, Sine Waves, and Exp-Log Curves

Hey Sara -- the flat fee difference of $6.25 would be made up by the $1.25 per day ...

Vivian L. answered • 10/05/13

Tutor

3
(1)
Microsoft Word/Excel/Outlook, essay composition, math; I LOVE TO TEACH

Hi Sara;

I can help you with the first question. Unfortunately, I do not have a graphing calculator.

A rental car agency charges a flat fee of $38.00 plus $2.75 per day to rent a certain car. Another agency charges a fee of $31.75 plus $4.00 per day to rent the same car.

x=quantity of days

$38.00+$2.75x=$31.75+$4.00x

We can cancel all $...

38.00+2.75x=31.75+4.00x

It is just as important to cancel symbols as numbers.

Next, we isolate x.

We will begin by subtracting 31.75 from both sides...

-31.75+38.00+2.75x=4.00x

6.25+2.75x=4.00x

Then, we will divide both sides by 4.00...

(6.25/4.00)+((2.75x)/4.00)=(4.00x)/4.00

1.56+0.69x=x

Then, we will subtract 0.69x from both sides...

-0.69x+1.56+0.69x=x-0.69x

1.56=0.31x

Then, we will divide both sides by 0.31...

1.56/0.31=(0.31x)/0.31

5=x

Let's check our numbers...

The original equation was...

$38.00+$2.75x=$31.75+$4.00x

38.00+2.75(5)=31.75+4.00(5)

38.00+13.75=31.75+20.00

51.75=51.75

Arthur D. answered • 10/05/13

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4.9
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Forty Year Educator: Classroom, Summer School, Substitute, Tutor

Rental Car Agency Problem

let x be the number of days

set up an equation

38+2.75x=31.75+4x (you want the costs to be equal)

38+2.75x-2.75x=31.75+4x-2.75x

38=31.75+1.25x

38-31.75=31.75-31.75+1.25x

6.25=1.25x

625=125x

625/125=x

5=x

answer: 5 days

check your work

38+2.75*5=38+13.75=$ 51.75

31.75+4*5=31.75+20=$ 51.75

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