Answer:
Angle A = 29°
Step-by-step explanation:
Remember one thing that when two secants intersect in the exterior of a circle then A=1/2(mDE-mBC) it means that the measure of the angle formed is one half the difference of the measures of the intercepted arcs
Now put the values in the equation.
A=1/2(mDE-mBC)
A=1/2(70-12)
A=1/2(58)
A = 29°
Thus angle A = 29° ....
