Answer
x = 11.2
Step-by-step explanation
To solve this, we need to use the Cosine rule
If a triangle XYZ has angles X, Y and Z at the points of the named vertices of the triangle with the sides facing each of these angles tagged x, y and z respectively, the Cosine rule is given as
x² = y² + z² - 2(y)(z) [Cos X]
For this question,
x = ?
y = 6
z = 10
X = 85°
x² = y² + z² - 2(y)(z) [Cos X]
x² = 6² + 10² - 2(6)(10) [Cos 85°]
x² = 36 + 100 - 120 [0.0872]
x² = 136 - 10.46
x² = 125.54
Take the square root of both sides
x = 11.2
Hope this Helps!!!