Given that x=7 and y=16 work out angle BCA

Can you me find the missing length. i attached an image.

Can someone plz me understand how to do these. plz, show work.in exercises 1-4, rewrite the expression in rational exponent form.[tex]\sqrt[4]{625} \sqrt[3]{512} (\sqrt[5]{4} )³ (\sqrt[4]{15} )^{7}\\ (\sqrt[3]{27} )^{2}[/tex]

Which linear function represents the line given by the point-slope equation y + 1 = –3(x – 5)?