Question 1087383
*[illustration GHI.png].
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{{{cos(GHI)=15/25=3/5}}}
{{{sin(GHI)=sqrt(1-cos^2(GHI))}}}
{{{sin(GHI)=sqrt(1-9/25)}}}
{{{sin(GHI)=sqrt(16/25)}}}
{{{highlight_green(sin(GHI)=4/5)}}}