Question 1171053

{{{(3/5)x - 4y = -1}}}-> both sides multiply by {{{5}}}
{{{0.8x - 3.5y = 1/2}}}-> both sides multiply by {{{10}}}
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{{{3x - 20y = -5}}}.........eq.1
{{{8x - 35y = 5}}}.........eq.2
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start with eq.1

{{{3x - 20y = -5}}}.........eq.1, solve for {{{x}}}

{{{3x=20y  -5}}}

{{{x=20y/3  -5/3}}}...........eq.1a

substitute in eq.2

{{{8(20y/3  -5/3) - 35y = 5}}}.........eq.2, solve for {{{y}}}

{{{160y/3  -40/3 - 35y = 5}}}-> both sides multiply by {{{3}}}

{{{160y  -40 - 105y = 15}}}

{{{160y- 105y = 15+40}}}

{{{55y =55}}}

{{{y =1}}}


go to eq.1a


{{{x=20y/3  -5/3}}}...........eq.1a, substitute {{{y}}}

{{{x=(20*1)/3  -5/3}}}

{{{x=20/3  -5/3}}}

{{{x=15/3}}}

{{{x=5}}}


solutions:{{{x=5}}},{{{y =1}}}