Question 935680


 the equations 

{{{3a+9b=8b-a}}} and 
{{{5a-10b=4a-9b+5}}} you can solve as a system using elimination
__________________

{{{3a+9b=8b-a}}}........eq.1 move all terms from the right side to the left
{{{5a-10b=4a-9b+5}}}........eq.2 
________________________

{{{3a+a+9b-8b=0}}}........eq.1
{{{5a-4a-10b+9b=5}}}........eq.2 
________________________


{{{4a+b=0}}}........eq.1
{{{a-b=5}}}........eq.2 
________________________...add both to eliminate {{{b}}}

{{{4a+cross(b)+a-cross(b)=5}}}

{{{5a=5}}}

{{{highlight(a=1)}}}

go to {{{4a+b=0}}}........eq.1 substitute {{{1}}} for {{{a}}}

{{{4*1+b=0}}}........eq.1

{{{4+b=0}}}

{{{highlight(b=-4)}}}