In figure, if AQ5cm, find the perimeter of triangle ABC

1.	In figure, if AQ5cm, find the perimeter of triangle ABC
Answer» Let PQ touch the circle at the point R. We know that tangents drawn from an external point to a circle are equal in length. AB = AC = 5cm AP +BP = AQ+ QC = 5cm AP + PR = AQ + QR = 5cm…………(1) [ BP = PR & QC = QR] Now, perimeter of ∆ APQ = AP +PQ+AQ = AP +RP+QR+AQ = 5 + 5 [ from eq 1] Perimeter of ∆ APQ= 10 cm

Answer»

Let PQ touch the circle at the point R.

We know that tangents drawn from an external point to a circle are equal in length.

AB = AC = 5cm

AP +BP = AQ+ QC = 5cm

AP + PR = AQ + QR = 5cm…………(1)

[ BP = PR & QC = QR]

Now, perimeter of ∆ APQ = AP +PQ+AQ

= AP +RP+QR+AQ

= 5 + 5 [ from eq 1]

Perimeter of ∆ APQ= 10 cm

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