Answer:
To find cosθ, use the formula for the area of a triangle i.e. AREA=1/2 x a x b x sinC.=> For this case: 15= 1/2 x 10 x 5 x sinC to find sinC.=> SinC = 3/5 thus, Arcsin(3/5)=+- 4/5 or +-0.8
To find the exact length of BC, use the cosine rule.=> c(sq)=a(sq)+b(sq)-2abCosC=> c(sq)=10(sq)+5(sq)-2(10)(5)(+-4/5)=> c(sq)= Square root of 205
Tree C is the proper tree. The first game has the possibility of a win, a loss, or a tie which the first row represents. The second game could also win, lose or tie, meaning each result would have each possibilty for that game.
Answer:

Step-by-step explanation:
using the sine rule,

Answer:
We only need one simple theorem for this.
Theorem 7 - The Exterior Angle Theorem: An exterior angle of a triangle is equal to the sum of the two remote interior angles.
So in this case, the measurement of the exterior angle is (45x)°, and the interior angles are (25x)° and (57 + x)°.
=> Therefore, we have:
25x + (57 + x) = 45x
25x + x - 45x = - 57
-19x = -57
x = -57/(-19) = 3
So x = 3