ABC is a triangle, right-angled at C. If AB = 25 cm and AC = 7 cm, find BC.


It is given in the question that,


AB = 25 cm


Also,


AC = 7 cm


We have to find BC



We know that,


According to Pythagoras theorem,


In a right angled triangle:


(Hypotenuse)2 = (Perpendicular)2 + (Base)2


By applying Pythagoras theorem in ABC, we get:


(AB)2 = (AC)2 + (BC)2


(BC)2 = (AB)2 - (AC)2


(BC)2 = (25)2 – (7)2


(BC)2 = 625 – 49


(BC)2 = 576


Hence,


QR =


QR = 24 cm


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