Answer:
Explanation:
Remark
The two angles with x in them are = 90 degrees. That's because this is a right angle triangle.
Equation
x^2 + 10x + 115 = 90 Subtract 90 from both sides
Solution for x
x^2 + 10x + 115 - 90 = 0
x^2 + 10x + 25 = 0
Factor
(x + 5)(x + 5) = 0
x = - 5
Angle C
C = 10x + 115
C = 10*-5 + 115
C = -50 + 115
C = 65
Angle A (which you don't need)
x^2 = (-5)^2
x^2 = A = 25
Find BC
Cos(C) = adjacent / hypotenuse
Cos(65) =0.4226
AC = hypotenuse = 65
0.4226 = adjacent / 44 Multiply both sides by 44
44 * 0.4226 = adjacent
adjacent = 18.6 to three places.