Question

If cos A = 4/5 , then the value of tan A is (A) 3/5 (B) 3/4 (C) 4/3 (D) 5/3

Answer 1

Answer:pls... understand care fully

cosA=4/5

then,

let base =4x, hypotenuse=5x

using Pyth$$€agoras theorem,

5x^2=perpendicular^2+4x^2

25x^2=p^2+16x^2

25x^2-16x^2=p^2

9x^2=p^2

p=3x

tanA=p/B

=3x/4x

= 3/4..

this is ur correct ans.

I hope it will help u...

Answer 2

Answer:

The value of tanA is 3/4.

Step-by-step explanation:

Given that

cos A=4/5

Consider that h is hypotenuse, p is perpendicular and b is Base of a right angle triangle.

We know

$cos \theta = \frac{b}{h}$

$tan \theta = \frac{p}{b}$

Therefore b=4 and h=5

From the Pythagoras theorem:

${p} = \sqrt{ {h}^{2} - {b}^{2} }$

$p = \sqrt{ {5}^{2} - {4}^{2} }$

$p = 3$

Therefore tanA = 3/4

Hence the option B is correct.