Where do the lines tangent to the circle intersect? After knowing this, use the corresponding formula.
y=80^(∘)
Practice makes perfect
Let's begin by drawing a diagram that illustrates the given situation.
We are given that x=260^(∘), which implies that m ADB is 260^(∘). Since CA and CB are tangent to the circle and they intersect each other outside it, we have that y is equal to one half the measure of the difference of the intercepted arcs.
y = 1/2(m ADB - m AB)
By using the measure of the major arc we will find the measure of the minor arc.
m ADB^(260^(∘)) + m AB = 360^(∘)
⇓
m AB = 100^(∘)
Finally, let's substitute the measures of both arcs to find the measure of the required angle.