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1 vote
A line parallel to a triangle's side splits AB into lengths of x - 7 and x - 3. The other side, AC, is split into lengths of x and x + 12. What is the length of AC?

User Mirko
by
8.5k points

2 Answers

7 votes

33


(x-7)/(x) = (2x-10)/(2x+12) → x =
(21)/(2)

AC = x + x + 12 =
(21)/(2) + (21)/(2) +12 = 33

User Glenn Stevens
by
7.7k points
2 votes
Given: x – 7 and x – 3 & AC is split into lengths of x and x + 12.

Solution:

(x – 7) / (x – 3) = x / (x + 12)

(x – 7) (x + 12) = x (x – 3)

x^2 + 5x – 84 = x^2 -3x

8x = 84

x = 10.5
Thus,

AC = x + x + 12

= 10.5 + 10.5 + 12

= 33 would be the length of AC
User Venkat Peri
by
8.5k points