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Solving pair of simultaneous (linear) equations

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In a workshop there are:

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In another workshop there are:

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Let \\(a\\) be the number of components that each machine of type A can manufacture per week and \\(b\\) be the number of components that each machine of type B can manufacture per week.

", "advice": "

a)  The equations can be constructed by careful reading of the question:

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\\( \\var{A1}\\)  machines of type A and   \\(\\var{B1} \\) machines of type B that can manufacture a total of \\(  \\var{T1} \\) components per week.

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Gives us:

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\\(  \\var{A1}a+\\var{B1}b=\\var{T1}  \\)

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In the same way, the second statement:

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\\( \\var{A2}\\)  machines of type A and   \\(\\var{B2} \\) machines of type B that can manufacture a total of \\(  \\var{T2} \\) components per week.

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Gives us:

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\\(  \\var{A2}a+\\var{B2}b=\\var{T2}  \\)

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b)  The most straightforward methods to solve this system of equations are \"Elimination\" or \"Substitution\".

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\"By Elimination\" involves multiplying the equations so that either the co-efficients of \\(a\\) are the same in both equations or the co-efficients of \\(b \\) are the same:

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For example, if we multiply the first equation by \\( \\var{A2} \\) and the second by \\( \\var{A1} \\) we get

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\\(  \\simplify{{A2}*{A1}a+{A2}*{B1}b={A2}*{T1}}  \\)

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\\(  \\simplify{{A1}*{A2}a+{A1}*{B2}b={A1}*{T2}}  \\)

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If we now subtract, term by term, one equation from the other we eliminate the terms in \\(a\\):

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\\(  \\simplify{(({A2}*{B1})-({A1}*{B2}))b = ({A2}*{T1})-({A1}*{T2})}  \\)

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\\( b = \\frac{\\simplify{({A2}*{T1})-({A1}*{T2})}}{\\simplify{(({A2}*{B1})-({A1}*{B2}))}} \\)

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\\( b=\\var{b}\\)

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We now have to go back to one of the original equations, use our value for \\(b\\) and calculate \\(a\\):

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\\(  \\var{A1}a+\\var{B1}b=\\var{T1}  \\)

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becomes:

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\\(  \\var{A1}a+\\var{B1}(\\var{b})=\\var{T1}  \\)

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\\(  \\var{A1}a+\\simplify{{B1}*{b}}=\\var{T1}  \\)

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\\(  \\var{A1}a=\\var{T1} -\\simplify{{B1}*{b}} \\)

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\\(  \\var{A1}a=\\simplify{{T1} -({B1}*{b})} \\)

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\\(  a=\\frac{\\simplify{{T1} -({B1}*{b})}}{\\var{A1}} \\)

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\\(  a=\\var{a} \\)

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Finally, we state our findings:

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Machine type A can produce \\( \\var{a} \\) components per week and Machine type B can produce \\( \\var{b} \\) components.

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c)  The best way to check your values is to substitute those values into BOTH, original equations and ensure that they \"balance\".

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Write down two simultaneous equations from the given information.

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The first equation uses the information from the first workshop:

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[[0]]

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The second equation can be writen using the information from the second workshop:

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[[1]]

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Solve these equations to find the number of components each type of machine can manufacture per week.

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\\(a=\\) [[0]]               \\(b=\\) [[1]]

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What would be a suitable method to check that the values you found are correct?

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