Question

Triangle X Y Z is shown. The length of X Y is 9, the length of Y Z is 19, and the length of X Z is y. Angle X Y Z is 41 degrees. Law of cosines: a2 = b2 + c2 – 2bccos(A) Which equation correctly uses the law of cosines to solve for y? 92 = y2 + 192 – 2(y)(19)cos(41°) y2 = 92 + 192 – 2(y)(19)cos(41°) 92 = y2 + 192 – 2(9)(19)cos(41°) y2 = 92 + 192 – 2(9)(19)cos(41°)

Answer 1

Choice D is correct

Explanation:

Just took the test

Answer 2

y² = 9² + 19² - 2(9)(19)Cos (41°)

Explanation:

Triangle X Y Z is shown.

The length of X Y is 9,

the length of Y Z is 19, and the length of X Z is y. Angle X Y Z is 41 degrees.

Law of cosines is given as:a²= b² + c² – 2bccos(A)

Applying this to Triangle XYZ, and since we are Solving for y

y² = x² + z² - 2xzCos Y

The length of X Y = x is 9,

the length of Y Z = y is 19

y²= 9² + 19² - 2(9 × 19)Cos (41°)

= y² = 9² + 19² - 2(9)(19)Cos (41°)

Option d is correct