Ten times a number, x, is one-half the sum of the number and three. which equations represents this situation?

x is variable or an unknown value to find

example:

2x = 5 which means x = 3

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.