need help on this !!!!!
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Answer:
17
Step-by-step explanation:
Remark
In this formation, the chords cut each other so that
Equation
(3x - 1) * 3 = 12*(x -2) Remove the brackets.
Solution
9x - 3 = 12x - 24 Add 24 to both sides.
9x - 3 + 24 = 12x - 24 + 24 Combine
9x + 21 = 12x Subtract 9x from both sides
9x - 9x +21 = 12x - 9x
21 = 3x Divide by 3
21/2 = 3x/3
7 = x
Find QR
QR = 12 + x - 2
QR = 10 + 7
QR = 17