Whats the domain of the graph of the function​

Isaac wants the equation below to have no solution when the missing number is placed in the box. which number should he place in the box?

You are riding your bike and notice the square sign above. you mentally draw a straight line from point a to c. describe the angle relationship between dca and bca

Given: δabc, m∠1=m∠2, d∈ ac bd = dc m∠bdc = 100º find: m∠a m∠b, m∠c