An isosceles triangle has two angles measuring 54.5 and 71.
What is the measure of the
third angle?

x=54.5

Step-by-step explanation:

54.5+71+x=180

125.5+x=180

x=54.5

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.