Acidity is measured on the pH scale. The acidity of a substance is given by pH=−logH, where H is the concentration of Hydrogen ions. If a substance has a pH of 6, which equation could be used to find its H value?

2/5

step-by-step explanation:

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.