Question 707688
Equation 1: {{{A = 10B}}}
Equation 2: {{{A - B = 81}}}
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Since equation 1 is already solved for A, plug 10B into equation 2 for A
Equation 2: {{{A - B = 81}}}
{{{(10B) - B = 81}}}
Combine like terms
{{{9B = 81}}}
Divide both sides by 9
{{{highlight(B = 9)}}}
Now plug 9 into equation 1 for B
Equation 1: {{{A = 10B}}}
{{{A = 10*(9)}}}
{{{highlight_green(A = 90)}}}