Respuesta :

Use the cos rule

cos^-1(18^2+28^2-12^2 divided by 2*18*28

Which is 16.99 degrees, which is 17 (option d)

Answer:

(D). 17 in.

Step-by-step explanation:

c² = a² + b² - 2abcosC

cosC = [tex]\frac{a^2 + b^2 -c^2}{2ab}[/tex]

m∠C = [tex]cos^{-1}[/tex] ( [tex]\frac{a^2 + b^2 -c^2}{2ab}[/tex] )

m∠C = [tex]cos^{-1}[/tex] ( [tex]\frac{28^2 +18^2 -12^2 }{2(28)(18)}[/tex] )

m∠C = [tex]cos^{-1}[/tex] ( [tex]\frac{964}{1008}[/tex] ) ≈ 17 in.

ACCESS MORE