Final answer:
To find the measure of angle AOC, subtract the measure of angle COB from angle AOB. Given that m∠AOB = 155° and m∠COB is 15° less than m∠AOC, we can set up the equation: m∠AOB - m∠COB = m∠AOC. By solving the equation, we find that m∠AOC ≈ 85°.
Step-by-step explanation:
To find the measure of angle AOC, we need to subtract the measure of angle COB from angle AOB. Given that m∠AOB = 155° and m∠COB is 15° less than m∠AOC, we can set up the equation: m∠AOB - m∠COB = m∠AOC. Substituting the given values, we have 155° - m∠COB = m∠AOC. Now we need to solve for m∠COB. We can set up another equation: m∠COB = m∠AOC - 15°. Substituting this into the first equation, we have 155° - (m∠AOC - 15°) = m∠AOC. Simplifying, we get 170° - m∠AOC = m∠AOC. Solving for m∠AOC, we find that m∠AOC ≈ 85°.