Question 707098
Equation 1: {{{A + B = 84}}}
Equation 2: {{{A - B = 30}}}
Solve equation 2 for A
{{{A = B + 30}}}
Now plug (B + 30) into equation 1 for A
Equation 1: {{{A + B = 84}}}
{{{(B + 30) + B = 84}}}
Combine like terms
{{{2B + 30 = 84}}}
Subtract 30 from both sides
{{{2B = 54}}}
Divide both sides by 2
{{{highlight(B = 27)}}}
Now plug 27 into equation 2 for B
{{{A = B + 30}}}
{{{A = (27) + 30}}}
{{{highlight_green(A = 57)}}}