Can someone help me with this. Will Mark brainliest. Need answer and explanation/work. Thank you.

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 equation using substitution. {4x + y = −2} {4x + 6y = 44}

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).