X to the second power=9x^2=9
The angles ABM and MBC sum to the measure of angle ABC. Let's create an equation to model the problem.
ABM + MBC = ABC
Let's plug our values into the variables.
ABM + 150 = 171
Let's solve for ABM. Subtract 150 from both sides.
ABM = 21
-9 and 6 add up to -3 and multiplies to -54