How to find the domain and range of numbers

In right ∆abc shown below, the midpoint of hypotenuse ac is located at d and segment bd is drawn.if ab = 12 and bc = 16, then explain why bd = 10. hint: consider what you know about the diagonals of a rectangle.

15 there is a line that includes the point 0,10 and has a slope of 7/4. what is it’s equation in slope intercept form

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.