Question

A triangle shows points A(2,8), B(14,4) and C(4,2). M is the midpoint of AC.
a. Write down the coordinates of M
b. Calculate the gradient of line AB.
c. Find the equation of the line parallel to AB that passes through M.

Answer 1

geez, impatient much?

Answer 2

a. M= [x1+x2/2,y1+y2/2] A=[2,8] C= [4,2]
=[2+4/2,8+2/2] = [6/3,10/2]= [3,5]
b. slope = y2-y1/x2-x1 A =[2,8] B = 14,4]
= 4-8/14-2 = -4/12 = -1/3

Answer 3

c. slope = -1/3, passing through [3,5]
equation of the line = [y-5] = -1/3[x-3]
= 3[y-5] = -1[x-3]
= 3y-15 = -x+3
= x+ 3y -18= 0