Answer:
43.8°
Step-by-step explanation:
Applying,
Cosine rule,
From the diagram attached,
x² = y²+z²-2yxcos∅.................... Equation 1
where ∅ = ∠YXZ
Given: x = 8.7 m, y = 10.4 m, z = 12.4 m
Substitute these values into equation 1
8.7² = 10.4²+12.4²-[2×10.4×12.4cos∅]
75.69 = (108.16+153.76)-(257.92cos∅)
75.69 = 261.92-257.92cos∅
collect like terms
257.92cos∅ = 261.92-75.69
257.92cos∅ = 186.23
Divide both sides by the coefficient of cos∅
cos∅ = 186.23/257.92
cos∅ = 0.722
Find the cos⁻¹ of both side.
∅ = cos⁻¹(0.7220)
∅ = 43.78°
∅ = 43.8°
Answer:

Step-by-step explanation:
Use the formula
to find the sum of the angles in a polygon, given <em>n</em> sides. This formula tells us the angles of this pentagon must add to 540 (
).
So, we can setup an equation:

Solve for z:
Combine like terms
Subtract 200
Divide by 5
Therefore, the value of z = 68.
Answer:
? = -36
Step-by-step explanation:
When you raise an exponent to an exponent, the resulting power is a product of the two exponents.
For this problem, you can solve for the missing value by writing:

Divide both sides by 1/3 to isolate the missing value.

Solve for ?.

your answer is C I'm definitely sure