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cute me

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need answer for number 14 on equations

13. Using the equation from number 12, if the electrician works 3 hours on a job, how much will the bill be?

13- y=45x+30
    y=45(3)+30
    y=135+30
    y=165

14. Using the equation from number 12, if you have a budget of 300.00 dollars for this job, what is the most full hours the electrician can work? Note: You want the largest number of hours without going over your budget:D

Bob

Administrator

Registered: 2010-06-20

Posts: 10,583

Re: need answer for number 14 on equations

hi cute me

I think you want y = 300 in the equation y = 45x + 30

So

300 = 45x + 30

subtract 30 from each side

270 = 45x

divide by 45

x = 270/45  = 6

So that's 6 hours

check 45 x 6 + 30 = 270 + 30 = 300

Bob

Last edited by Bob (2011-06-02 09:37:27)

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