Question 1080313
{{{x^2+y^2-2xy*cos(Z)=z^2}}}


{{{-2xy*cos(Z)=z^2-x^2-y^2}}}

{{{cos(Z)=(z^2-x^2-y^2)/(-2xy)}}}

{{{cos(Z)=(x^2+y^2-z^2)/(2xy)}}}

{{{cos(Z)=(19.1^2+32.7^2-41.2^2)/(2*19.1*32.7)}}}

{{{cos(Z)=-0.21081704}}}


Measure of angle at point Z,   102.2 degrees