16 is the original distance her dance class was from home
Check the angle. If it they are less than 90°<span> , so they will result in acute angles. </span>
Cross multiply the expression so that we can get
(1+sinx)(1-sinx) = cos^2 x
1 - sin^2 x = cos^2 x
cos^2 x + sin^2 x = 1
since
cos^2 x + sin^2 x = 1
therefore
1 = 1
the two expressions are identical in a trigonometric sense
