Question

find ( moverarc{bc} ).
( moverarc{bc} = square^circ )

Explanation:

Step1: Sum of circle's arcs is 360°

Let $m\overset{\frown}{BC} = x$. The total of all arcs equals $360^\circ$.

Step2: Set up the equation

$$64^\circ + 114^\circ + x + 142^\circ = 360^\circ$$

Step3: Calculate known arc sum

$$64 + 114 + 142 = 320$$

Step4: Solve for $x$

$$x = 360^\circ - 320^\circ$$

Answer:

$40$