Help please I'm confused​

Which of these equations, when solved, gives a different value of x than the other three? a9.1 = -0.2x + 10 b10 = 9.1 + 0.2x c10 – 0.2x = 9.1 d9.1 – 10 = 0.2x

Solve this riddle: i am an odd number. i an less than 100. the some of my digit is 12. i am a multiple of 15. what number am i?

Which statements describe the solutions to the inequality x< -20 check all that apply. there are infinite solutions. each solution is negative. each solution is positive. the solutions are both positive and negative. the solutions contain only integer values. the solutions contain rational number values.