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If the points (-1, t -1), (t, t - 3) and (t - 6, 3) lie o...

If the points (-1, t -1), (t, t - 3) and (t - 6, 3) lie on the same straight line, find the values of t.

A.

t = -2 and 3

B.

t = 2 and -3

C.

t = 2 and 3

D.

t = -2 and -3

Correct answer is C

For collinear points (points on the same line), the slopes are equal for any 2 points on the line.

Given (-1, t - 1), (t, t - 3), (t - 6, 3), 

slope=(t3)(t1)t(1)=3(t3)(t6)t=3(t1)(t6)(1)

Taking any two of the equations above, solve for t.

t3t+1t+1=6t6

12=(6t)(t+1)

t2+5t+612=0t25t+6=0

Solving, we have t = 2 and 3.