How do I solve this questions

2y= 3 2 x−2 y = − 1 3 x + 1 y=− 3 1 x+1

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?

Ms. green tells you that a right triangle has a hypotenuse if 13 and a leg of 5. she ask you to find the other leg of the triangle. what is you're answer?