मराठी

In the Given Figure. Pq = Ps, P =R = 90°. Rs = 20 Cm and Qr = 21 Cm. Find the Length of Pq Correct to Two Decimal Places. - Mathematics

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प्रश्न

In the given figure. PQ = PS, P =R = 90°. RS = 20 cm and QR = 21 cm. Find the length of PQ correct to two decimal places.

बेरीज
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उत्तर


In ΔSRQ, ∠R = 90°
∴ QS2 = RS2 + QR2     ....(Pythagoras Theorem)
= 202 + 212
= 440 + 441
= 841
Now,
In ΔQSP, ∠P = 90°
∴ QS2 = PQ2 + PS2
⇒ QS2 = PQ2 + PQ2     ....(Pythagoras Theorem)
⇒ QS2 = 2PQ2              ....(Given PQ = PS)

⇒ PQ2 = `"QS"^2/(2) = (841)/(2)` = 420.5
⇒ PQ = 20.50cm.

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 17: Pythagoras Theorem - Exercise 17.1

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फ्रँक Mathematics [English] Class 9 ICSE
पाठ 17 Pythagoras Theorem
Exercise 17.1 | Q 23

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