Question

In △ABC given below, the altitude CD =2√3 cm, BC=4 cm and AD=2√3 cm.
Find the following:

∠B=
°
∠A=
°
∠BCA=

Answer 1

Step-by-step explanation:

Two equilateral triangles can be termed with the base AB.

But vertex D should be at maximum distance from C.

Therefore, triangle ABD will be preferred.

Now,ΔABD is equilateral triangle.

∴AB=BD=AD=103cm

In right ΔABC

(BC)2=(AB)2+(AC)2

(20)2=(103)2+(AC)2

(AC)2=400−300

AC=10

In ΔACD,∠CAD=900+600=1500

cos∠CAD=2(AD)(AC)(AD)2+(AC)2−(CD)2[∵cosC=2aba2+b2−c2]

cos65π=2(103)(10)1032+