In RT triangle ABC, angle B = 90 ', ab = 6 cm, BC = 8 cm. Point P starts from a and follows ab If points P and Q start from points a and B at the same time, then after a few seconds, the distance between two points P and Q is 53 cm? I use words to describe the symbols. Please read the meaning of the words clearly. Write the equation of one variable and degree
Let the distance between P and Q be 53 cm after x seconds,
Then in the right triangle PBQ, Pb = ab-ap = 6-x, BQ = 2x
According to Pythagorean theorem, Pb * Pb + BQ * BQ = PQ * PQ
(6-X)(6-X)+2X*2X=53
5X^2-12X-17=0
(X+1)(5X-17)=0
X = 17 / 5, (x = - 1, rounded off.)
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