Question 566566
{{{y=5x+5}}}........(1)
{{{y=15x-1}}}.......(2)
Substitute the value of y from (2) to (1) 
{{{15x-1=5x+5}}}
{{{15x-5x=5+1}}}
{{{10x=6}}}
{{{10x/10=6/10}}}
{{{cross(10)x/cross(10)=cross(6)/cross(10)}}}
{{{x=3/5}}}
Put the value of x in (1)
{{{y=5x+5}}}........(1)
{{{y=5(3/5)+5}}}
{{{y=cross(5)(3/cross(5))+5}}}
{{{y=3+5}}}
{{{y=8}}}


x,y = 3/5, 8


Check
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Put the value of x and y in (1)
{{{y=5x+5}}}........(1)
{{{8=5(3/5)+5}}}
{{{8=5(3/5)+5}}}
{{{8=cross(5)(3/cross(5))+5}}}
{{{8=3+5}}}
{{{8=8}}}
Put the value of x and y in (2)
{{{y=15x-1}}}
{{{8=15(3/5)-1}}}
{{{8=cross(15)(3/cross(5))-1}}}
{{{8=(3)(3)-1}}}
{{{8=9-1}}}
{{{8=8}}}