Question 1110348
{{{system(x=10,y=30,r__hyptoenuse)}}}


{{{r^2=100+900=1000}}}

{{{r=sqrt(1000)}}}

{{{r=10*sqrt(10)}}}

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g, the measure of angle at the ground, shadow meets ground;
{{{cos(g)=10/(10*sqrt(10))}}}


{{{cos(g)=1/sqrt(10)}}}


{{{cos(g)=sqrt(10)/10}}}


g, arcWhoseCosineIs {{{sqrt(10)/10}}}


{{{g=cos^(-1)(0.3162)}}}


{{{highlight_green(g=72*degrees)}}}