Polly walked a total of 20 kilometers by making 4 trips to school. How many trips will Polly have to make in all to walk a total of 50 kilometers? Assume the relationship is directly proportional.

The first is 6.1 using the distance formula.
distance = sqrt((x2-x1)^2+(y2-y1)^2)
plug it all in and simplify
you get 6.1

the next one is the midpoint. u just take add both values of x together and divide by 2 to get the x coordinate and then add together both values of y and divide by 2 to get the y value. the midpoint is (8,7)

to find the perimeter of the rectangle, add the lengths of each side. 25 for the height and you would add 2 of those and then there are 2 sides as long as the length that you would add. it would be height+height+length+length which is 25+25+77+77=204. remember units so 204 ft