Question

y In triangle IS ABC .LA = 900 - find the length If of AC & AB​

Answer 1

Answer:

So, △ABC is Right-angled isosceles.

∠B=∠C ...(angles opp. to equal sides are equal)

∠A+∠B+∠C=180

∘

...(angle - sum property of a triangle)

Substituting ∠B=∠C, ∠A=90

o

90

∘

+2∠B=180

∘

2∠B=180

∘

–90

∘

=90

∘

⇒∠B=45

∘

So, ∠C=∠B=45

o

.

Answer 2

Answer:

Given, ∠A=90

∘

By Pythagoras theorem,

BC

2

=AB

2

+AC

2

BC

2

=5

2

+12

2

BC=13 cm

Area of triangle =

2

1

×base×height

Thus,

2

1

AB×AC=

2

1

AD×BC

5×12=13×AD

AD=

13

60

cm.

solution