Question

pls help me with the circled one....

Answer 1

We know that the area of the any triangle is half of the product of it's perpendicular and base.

Now,

First taking side QR as the base and PM as the perpendicular height.

So,

Area of the triangle = 1 / 2 x QR x PM

= > Area = 1 / 2 x 10 cm x 4.4 cm

= > Area = 1 / 2 x 44 cm^2

= > Area = 22 cm^2

Then,

Taking PR as the base and QN as the perpendicular height.

So,

Area of triangle = 1 / 2 x PR x QN

= > Area = 1 / 2 x 11 cm x QN

= > Area = 11 / 2 cm x QN

From above, area of the triangle = 22 cm^2 . Substitute the value of area in 11 / 2 cm x QN.

= > 22 cm^2 = 11 / 2 cm x QN

= > 22 cm^2 / 11 = 1 / 2 cm x QN

= > 2 cm^2 = 1 / 2 cm x QN

= > 2 x 2 cm^2 / cm = QN

= > 4 cm = QN

Therefore the altitude QN measures 4 cm.

Hence, option ( 1 ) is correct.