Practicing Success
In a ΔABC, the bisectors of ∠B and ∠C meet at O. If ∠BOC = 142°, then the measure of ∠A is: |
52° 68° 104° 116° |
104° |
Let \(\angle\)B x and \(\angle\)C = y OB and OC are two angle bisectors and meets at O In \(\Delta \)BCO, \(\frac{x}{2}\) + \(\frac{y}{2}\) + 142 = 180 = \(\frac{x}{2}\) + \(\frac{y}{2}\) = 38 = x + y = 76 In \(\Delta \)ABC, \(\angle\)B + \(\angle\)C = 76 \(\angle\)A = 180 - 76 = \(\angle\)A = 104 Therefore, \(\angle\)A is \({104}^\circ\). |