SOLUTION: I am 50 yrs old, haven't used algebra since High School and now need it and can't remember what to do to solve the following equations for B and for N:
0.63B + 0.37N = -8.4 and
Question 334974: I am 50 yrs old, haven't used algebra since High School and now need it and can't remember what to do to solve the following equations for B and for N:
0.63B + 0.37N = -8.4 and 0.56B + 0.44N = -6.6
I know I need to pick one of the equations, determine the equation just for N, and then replace N in the other equation with that formula to solve for B. eg, for the first equation 0.37N = -8.4 - 0.63B, now I am stuck as to how to solve for B? Is it N = (-8.4 - 0.63B)/0.37? How do I perform the calculation to solve for B? Found 4 solutions by stanbon, nerdybill, solver91311, priyaasai:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 0.63B + 0.37N = -8.4
0.56B + 0.44N = -6.6
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Multiply thru each equation by 100 to get rid of the decimals:
63B + 37N = -840
56B + 44N = -660
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Multiply thru the 1st equation by 56
Multiply thru the 2nd equation by 63
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56*63B + 56*37N = 56*-840
63*56B + 63*44N = 63*-660
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Subtract the 1st equation from the 2nd and solve for "N":
700N = 5460
N = 7.8
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Substitute into 56B+44N=-660 and solve for "B":
56B+44(7.8)=-660
56B = 1003
B = 17.9143
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Cheers,
Stan H.
Now take the right hand side mess and replace N in the second equation.
Now you have an equation, albeit an extremely ugly one, in one variable that can be solved by ordinary algebraic means. Once you have a value for , you can substitute that value back into either of the original equations to produce a single-variable equation in .
This is mostly just nasty arithmetic. Enjoy.
John
My calculator said it, I believe it, that settles it
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