Question

Triangle LMN is right angled at M. If LN = 17cm & LM = 8cm. Find MN.

Answer 1

Answer:

ANSWER

LM=9cm

MN=12cm

LN=15cm

∴PM=4.5cm

QN=7.5cm

And we know that the line joining the mid points of the two sides of a triangle is parallel to the third side and is equal to half of it.

∴PQ=

2

1

MN=6cm

(i)Perimeter of trapezium MNQP=(4.5+7.5+12+6)

=24+6

=30cm

(ii)Area of trapezium=

2

1

×(sum of parallel sides)× (height)

=

2

1

×(12+6)×4.5

=9×4.5

=40.5cm

Answer 2

Answer:

MN =15cm

Step-by-step explanation:

Using Pyathagoras Theorem on triangle LMN

LN²=LM²+MN²

17²=8²+MN²

289=64+MN²

289-64=MN²

225=MN²

15²=MN²

Taking square root on both sides

15=MN