What is the point of concurrency of the altitudes of a triangle

Aconvex octagon has interior angles that measures 73 degrees, 172 degrees, 132 degrees, 59 degrees, 154 degrees, 163 degrees, x degrees, 2x degrees find the value of the missing angles

Cassie is traveling 675 miles today to visit her brother and his family. so far, she has stopped for gas three times. at the first stop, she put in 7.1 gallons of gas and paid $23.79. at her second stop, she put in 5.8 gallons of gas and paid $19.08. and, at the third stop, 6.6 gallons and paid $20.39. at which stop did casey pay the most for gas?

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)