"to find the perimeter of the triangle we require to"
"calculate the lengths of the 3 sides"
"perimeter "=AB+AC+BC
color(blue)"calculate AB"
"Note that the points A and B have the same value of"
"x-coordinate which means that AB is a vertical line"
"Thus the length of AB is the difference in y-coordinates"
rArrAB=6-2=4
color(blue)"calculate BC"
"Note that the points B and C have the same value of "
"y-coordinate which means that BC is a horizontal line"
"Thus the length of BC is the difference in x-coordinates"
rArrBC=3-(-3)=6
color(blue)"calculate AC"
"to calculate AC use the "color(blue)"distance formula"
•color(white)(x)d=sqrt((x_2-x_1)^2+(y_2-y_1)^2)
"let "(x_1,y_1)=(-3,6)" and "(x_2,y_2)=(3,2)
AC=sqrt((3+3)^2+(2-6)^2)
color(white)(AC)=sqrt(36+16)=sqrt52
rArr"perimeter "=4+6+sqrt52~~17.21" to 2 dec. places"
