Question 298388
Set-Up:
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Equation 1: {{{A + B = 16}}}
Equation 2: {{{2A - B = -1}}}
Solution:
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Solve equation 1 for one of the variables
Equation 1: {{{A + B = 16}}}
{{{B = 16 - A}}} i solved for B, now plug (16-A) into equation 2 for B
Equation 2: {{{2A - B = -1}}}
{{{2A - (16 - A) = -1}}} Simplify
{{{3A - 16 = -1}}} Add 16 to both sides
{{{3A = 15}}} Divide both sides by 3
{{{highlight(A = 5)}}}

Now plug 5 into equation 1 for A
{{{B = 16 - A}}}
{{{B = 16 - 5}}}
{{{highlight(B = 11)}}}