Question

If ΔABC ~ ΔQRP, ar (ΔABC) / ar (ΔPQR) =9/4 , AB = 18 cm and BC = 15 cm, then PR is equal to

(A) 10 cm (B) 12 cm (C) 20/3 cm (D) 8 cm

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Answer 1

⠀⠀ıllıllı uoᴉʇnloS ıllıllı

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Given that:

• ΔABC ~ ΔQRP.

ar (ΔABC) / ar (ΔPQR) = 9/4

AB = 18 cm and BC = 15 cm

We know that:

The ratio of the areas of two similar triangles is equal to the square of the ratio of their corresponding sides.

ar (ΔABC) / ar (ΔPQR) = BC²/RP²

9/4 = (15)²/RP²

RP² = (4/9) ×225

PR² = 100

Therefore,

• PR = 10 cm

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Answer 2

Answer:

10

Step-by-step explanation:

Given that ΔABC ~ ΔQRP.

ar (ΔABC) / ar (ΔQRP) =9/4

AB = 18 cm and BC = 15 cm

We know that the ratio of the areas of two similar triangles is equal to the square of the ratio

of their corresponding sides.

ar (ΔABC) / ar (ΔQRP) = BC2

/RP2

9/4 = (15)2

/RP2

RP2 = (4/9) ×225

PR2 = 100

Therefore, PR = 10 cm