With reference to the diagram, which conclusion can be drawn correctly from the premises? a) ac = co b) oa + ob + ab > ∠bac c) m∠aco < 45° d) m∠bac = 90°

Applying premise I, OA = OB and OA = OC.

Applying premise II, to ΔOAB, m∠OAB = m∠ABO = m∠ABC.

Applying premise III, to ΔOAC, m∠OAC = ∠ACO = m∠ACB.

Now on application of premise III, it follows that:

2 m∠ABC + 2 m∠ACB = 180° ⇒ m∠ABC + m∠ACB = 90°

50-60=10

step-by-step explanation:

180-142=38 for the acute angle next to the entry

90+38=128

180-128=52

a=52

step-by-step explanation: