Question

in the adjoining figure ABC,AngleB=90,AngleA=30and BC=6cm .find ABand AC​

Answer 1

Answer:

since BC=6cm and angle B =90°

using tan30°=1/√3

BC/Ab=1/√3

AB=√3BC=6√3

now by Pythagoras Theorem

AC^2=BC^2+AB^2

= 36×3+36

=36×4

therefore AC=√36×√4 =12

hope it's right

Answer 2

Given :-

• In the figure ABC is a right angle in which angleB=90°, BC=6cm and angleA= 30°

To Find :-

• Length of AC

Solution :-

• Sum of all angle in a triangle = 180

A + B + C = 180

30 + 90 + C = 180

120 + C = 180

C = 180/120

C = 60

Now,

$\longrightarrow$Length of AC =

$\longrightarrow$sin A = BC/AC

$\longrightarrow$sin (30) = BC/AC

As sin 30 = 1/2

$\longrightarrow$1/2 = BC/AC

$\longrightarrow$2BC = 1(AC)

$\longrightarrow$2BC = AC

$\longrightarrow$2(6) = AC

$\longrightarrow$12 = AC