  Question:

In triangle PQR, angle q=90 degree. If PQ=12 cm and PR=13 cm find the area of triangle PQR

Posted by: Siddhangana D. on 26.08.2020 Raj K. from Patna
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Given, PQR is a triangle and <Q =90 degree

And PQ = 12 cm

PR = 13 cm

We know that the area of right angle triangle = 1/2 ( product of legs)

But one leg QR is not given here

So by Pythagores theorem

(PQ)^2 + (QR)^2 = (PR)^2

= (12)^  + (QR)^2 = (13)^2

= 144 + (QR)^2    =169

So, (QR)^2= 169-144

or, (QR)^2=25

so, QR = 5 cm

Now Area of right anged triangle PQR= 1/2 X 5 X 12 • Like

Answer:  5,12&13 form a pythagorean triplets.Given  PR=13 cms amd PQ= 12 cms it follows that side

QR of the triangle =5cms. As PR =13 cms is the hypotenuse , the other two are the sides

Therfore  the area  of the triangle PQR = 1/2*PQ*QR  =1/2*12*5= 30 Sq.cm S.Chandra from Kolkata
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Applying Pythagoras theorem, QR= root(PR^2 - PQ^2) = root(13^2 - 12^2) cm = root(25) cm = 5 cm .

Hence, area of triangle PQR = (1/2).PQ.QR = (1/2).12.5 cm^2 = 30 cm^2 .   (Ans.) Deepali P. from Noida
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By using 1/2 *BASE*HIEGHT formula we can find area of triangle but, We know about only two sides so, first we have to find the 3rd side i.e. QR(base) Lest assume QR = a cm R
Rohit R. from Jamshedpur
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Applying Pythaagoras Theorem.

Third side will be 5cm.

So area = 1/2 * 5 * 12 = 30 square cm.

R
Rohit R. from Jamshedpur
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Using Pythagoras theorem the third side will be 12cm. Area = (1/2) * 5*12 =30square cm Nitesh J. from Delhi
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Are =1/2 Base x Perpendicular Area of pqr = 1/2x5x12 30unit ### Post Answer and Earn Credit Points

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