Question

Question. 1 :
In ∆ ABC, right-angled at B, AB = 24 cm, BC = 7 cm.

Question 2:
If Sin A = 3/4, Calculate cos A and tan A.

Mathematics
Class 10.
Quality Answer Required .

Explain your answer .​

Answer 1

Answer to Question 1:

AB = 24cm

BC = 7cm

∠B = 90°

AC = ?

Using Pythagoras theorem:  

AC² = AB² + BC²

AC² = 24² + 7²

AC² = 576 + 49

AC = √625

AC = 25

Answer to Question 2:

SinA = 3/4

CosA = ?

TanA = ?

SinA = Opp. side/Hypotenuse

= 3/4

(Construct a triangle right angled at B with one side BC of 3cm and hypotenuse AC of 4cm.)

Using Pythagoras theorem:  

AC² = AB² + BC²

4² = AB² + 3²

16 = AB + 9

AB = √7cm

CosA = Adjacent side/Hypotenuse

= AB/AC

= √7/4

TanA = Opp. side/Adjacent side

= BC/AB

= 3/√7

Answer 2

Question:-

• In ∆ ABC, right-angled at B, AB = 24 cm, BC = 7 cm.

Given:-

• Right-angled at B, AB = 24 cm, BC = 7 cm.

Solution:-

Here ,

We have to use Pythagoras Theorem:-

AC² = AB² + BC²

AC² = 24² + 7²

Ac² = 576 + 49

AC = √625

AC = 25