solve all questions.

[In Problems 19 and 20. use a calculator to find the distance be- tween the two points. Round off your answer to three decimal places. 19 (-2.714. 7.11 1) and (3.135, 4.982) 20 (#. ) and (-V17. '') In Problems 21 to 24. (a) use the distance formula and the converse of the Pythagorean theorem to show that triangle ABC is a right triangle, and (b) find the area of triangle ABC. 21 A = (1. 1). B = (5. 1), C = (5. 7) 22 A = (-1. -2). 8 = (3. -2). C=(-1. -7) 23 A = (0. 0). 8 = (=3, 3). C = (2, 2) 24 A = (-2, -5). B = (9. 1). C = (4. ") 25 Show that the points A = (-2, -3). 8 = (3. -1). C = (1. 4). and D = (-4. 2) are the vertices of a square. 26 Show that the distance between the points ($1. y,) and (x?. ya) is the same as the distance between the point ( - x3. ) - 32) and the origin. 27 If A = (-5. 1). 8 = (-6, 5), and C = (-2, 4). determine whether triangle ABC is isosceles