Question 461843


{{{15x + 5y=185}}}......1 
{{{-4x+5y=-5}}} .........2....subtract from 1
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{{{15x + 5y=185}}}......1 
-
{{{-4x+5y=-5}}} .........2
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{{{15x-(-4x)+ 5y- 5y=185-(-5)}}}

{{{15x-(-4x)+ cross(5y)- cross(5y)=185-(-5)}}}

{{{15x+4x =185+5}}}

{{{19x =190}}}

{{{x =190/19}}}

{{{x =10}}}

now find {{{y}}}

{{{15x + 5y=185}}}......1 


{{{15*10 + 5y=185}}}

{{{150 + 5y=185}}}

{{{ 5y=185-150}}}

{{{ 5y=35}}}

{{{ y=35/5}}}

{{{ y=7}}}

check:


{{{15x + 5y=185}}}......1 

{{{15*10 + 5*7=185}}} 

{{{150 + 35=185}}} 

{{{185=185}}} 

{{{-4x+5y=-5}}} .........2

{{{-4*10+5*7=-5}}} 

{{{-40+35=-5}}} 

{{{-5=-5}}}