1/2a-10b=c solve for a Multiply each side of the equation by 2: 2/2a - 2(10)b = 2c Simplify: a - 20b = 2c Add 20b to each side: a - 20b + 20b = 2c + 20b Cancel the 20b on the left side: a = 2c + 20b You can also factor out a 2 on the left side for another version of this answer: a = 2(c + 10b)