In ∆PQR, PR = 8 cm, QR = 4 cm and PL = 5 cm. Find: (i) the area of the ∆PQR (ii) QM. - Mathematics

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Sum

In ∆PQR, PR = 8 cm, QR = 4 cm and PL = 5 cm.

Find:
(i) the area of the ∆PQR
(ii) QM.

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Solution

(i) QR = base = 4 cm, PL = height = 5 cm

Area of the triangle PQR =`1/2bh`

= `1/2 xx 4 xx 5` 

= 10 cm2

(ii) PR = base = 8 cm, QM = height = ?, Area = 10 cm2

Area of triangle = `1/2 xx b xx h`

10 = `1/2 xx 8 xx h`

h = `10/4 = 5/2 = 2.5`.

QM = 2.5 cm

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