Explanation:
1) As U is the mid point of TV ,it divides the whole line in two equal parts:
TV=TU+UV
TU=UV
Subtitute values:
5x+6=23+23
5x+6=46
5x=46-6
5x=40
x=40/5
x=8
2) Q is mid point of PR so PQ=QR
PR=PQ+QR
15x-29=6x-1+6x-1
15x-29=12x-2
15x-12x=29-2
3x=27
x=27/3
x=9
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