Find the value of x so that ST is parallel to PR.
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if ST is parallel to PR than triangle PRQ and triangle STQ will be congurent
and now using property of congurent triangle
RQ/PQ = TQ/SQ
(4x-3+3)/(25+5)= 3/5
4x/30 = 3/5
4x = 3×30/5= 18
x = 18/4 = 9/2
x = 4.5