Congruent angles formed by two intersecting lines

the intersecting lines forms pair corresponding angles

adjacent angles vertically opposite angle

hope it will help you

the answer is 99.

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.