Diego solved an equation by multiplying both sides by 6. Then he checked that 6 is the correct solution by substituting it back into the original equation. Which of the following gives the properties of equality that he used and their correct order?

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.

x = 3 ± √(5+y)

i think the answer is b