Question 914458

{{{2x + y = - 7}}} .........eq.1
{{{y = 3x + 8}}} ...........eq.2....substitute {{{y}}} in eq.1
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{{{2x + (3x + 8) = - 7}}} .........eq.1...solve for {{{x}}}

{{{2x + 3x + 8 = - 7}}}

{{{5x= - 7-8}}}

{{{5x= -15}}}

{{{x= -15/5}}}

{{{highlight(x= -3)}}}

go back to eq.2,substitute {{{x}}} and solve for {{{y}}}


{{{y = 3(-3) + 8}}} ...........eq.2....


{{{y = -9 + 8}}}

{{{highlight(y = -1)}}}

{{{ graph( 600, 600, -10, 10, -10, 10, -2x-7, 3x + 8) }}}