Writing equations for substitution and elimination.

Simplificatation, evaluation, linear equations, linear graphs, linear inequalities, basic word problems, etc.
Jsnxt32
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Joined: Wed Oct 20, 2010 4:04 am
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Writing equations for substitution and elimination.

Postby Jsnxt32 » Wed Oct 20, 2010 4:12 am

I am trying to complete a checkpoint for class and need a couple clues for the world problems. I always have a problem with word problems. It's about buying houses;
a. sales rep. states there 56 houses for sale with two floor plans available. x is floor plan one, y is floor plan two. what equation illustrates this?

Is it x + y = 56 ?

b. sales rep. states there are three times as many homes available with floor plan two versus floor plan one. what equation illustrates this?

Is is x = 3y - 56 ?

Use substitution to determine how many of each floor plan is available.

Stranger_1973
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Joined: Sun Feb 22, 2009 9:56 pm

Re: Writing equations for substitution and elimination.

Postby Stranger_1973 » Wed Oct 20, 2010 8:28 pm

I agree with (a) but how did you get (b)? What was your reasoning?

Jsnxt32
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Joined: Wed Oct 20, 2010 4:04 am
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Re: Writing equations for substitution and elimination.

Postby Jsnxt32 » Thu Oct 21, 2010 2:21 pm

Part b is just a continuance of part a. The sales rep showing the houses stated that there are three times as many homes available in floor plan two, then floor plan one. The two separate equations are to be combined and figured through substitution, this is in order to figure out how many of each house there is.

Stranger_1973
Posts: 21
Joined: Sun Feb 22, 2009 9:56 pm

Re: Writing equations for substitution and elimination.

Postby Stranger_1973 » Thu Oct 21, 2010 9:45 pm

Okay. You have x=plan 1 and y=plan 2. You have plan 1 is 3*(plan 2). How did you get "plan 1 is 3*(plan 2) less 56"?

Use the variagles instead & plug them into "plan 1 is 3*(plan 2)" just like you did for "the sum of plan 1 and plan 2 is 56".


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