I need the answers for all three of those

Aperpendicular bisector, cd is drawn through point con ab if the coordinates of point a are (-3, 2) and the coordinates of point b are (7,6), the x-intercept of cd is point lies on cd.

Suzanne began a trip with 18 1/2 gallons of gas in the gas tank of her car if she hughes 17 3/4 gallons on the trip how many gallons does she have left once she finish the trip

Aright triangle has an area of 21 m2. the dimensions of the triangle are increased by a scale factor of 4. what is the area of the new triangle