Question 946957

{{{.5x + y = 9 }}}..........eq.
{{{1.6x + 0.2y = 13}}}......eq.2
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{{{.5x + y = 9 }}} solve for {{{y}}}

{{{ y = 9-.5x }}}....substitute in eq.2


{{{1.6x + 0.2(9-.5x) = 13}}}......eq.2 solve for {{{x}}}

{{{1.6x + 1.8-0.1x = 13}}}

{{{1.6x-0.1x = 13-1.8}}}

{{{1.5x = 11.2}}}...multiply by {{{10}}}

{{{15x = 112}}}

{{{x = 112/15}}}

{{{x = 7.466666666666667}}}

{{{x = 7.5}}}

go to {{{ y = 9-.5x }}}, substitute {{{7.5}}} for {{{x}}} and solve for {{{y}}}

{{{ y = 9-.5*7.5 }}}

{{{ y = 9-3.75 }}}

{{{ y = 5.25 }}}