Question 198885
Please solve by the elimination method.
<pre><font size = 4 color = "indigo"><b>
{{{system(5r-6s = 21, 6r+5s = 74)}}}

Eliminate s by multiplying the top equation by 5 and
the bottom equation through by 6

{{{system(5(5r-6s) = 5(21), 6(6r+5s) = 6(74))}}}

{{{system(25r-30s = 105, 36r+30s = 444)}}}

Now add corresponding terms:

{{{61r+0s=549}}}

{{{61r=549}}}

{{{r=549/61}}}

{{{r=9}}}

Now switch over to substitution to find s

{{{5r-6s = 21}}}

{{{5(9)-6s=21}}}

{{{45-6s=21}}}

{{{-6s=21-45}}}

{{{-6s=-24}}}

{{{s=(-24)/(-6)}}}

{{{s=4}}}

So (r,s)=(9,4)

Edwin</pre>