Question

If `cosA=3/10` what is `tanA`?

Answer 1

`tanA=sqrt(91)/3`

Explanation:

Since the cosine ratio is the adjacent over the hypotenuse, we can use the Pythagorean Theorem to solve for the third side (opposite leg). `3^2+y^2=10^2`
So, `y^2=100-9` or `y^2=91`
then, `y=sqrt(91)`.

Tangent of angle A will be: `sqrt(91)/3`