The value of x is 5, if a, b, and c are collinear points.
According to the given question.
a, b, and c are collinear points.
Which means points a, b, and c both lie in a same line.
b is between a nd c .
Also, ab = 12
bc = 5x - 2
and ac = 3x + 20
Since, b lies in between a and c
Therefore,
ab + bc = ac
12 + 5x - 2 = 3x + 20
⇒ 10 + 5x = 3x + 20
⇒ 5x - 3x = 20 - 10
⇒ 2x = 10
⇒ x = 10/ 2
⇒ x = 5
Therefore, the value of x is 5.
Find out more information about collinear points here:
brainly.com/question/5191807
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