Given that sinθ=3/5 , what is cosθ?

Question

Hero · Answer

So in this case, the same rules apply except all you need to know in this case is that
$\sin(\theta) = \dfrac{a}{c}$ and $\cos(\theta) = \dfrac{b}{c}$ and

Pythagorean Theorem:
$a^2 + b^2 = c^2$

princeevee · Answer

@Hero

princeevee · Answer

@Vocaloid

Hero · Answer

That doesn't apply here @princeevee

Hero · Answer

You only need to use what I have given you above. The other stuff only applied to other problem. Doesn't apply here except for what is above.

princeevee · Answer

so it's given that a=3 and b=5?

Hero · Answer

actually a = 3 and c = 5

princeevee · Answer

oh right, sorry, so a is 3, and b is x as of now

Hero · Answer

or rather b is "unknown"

princeevee · Answer

c^2 = 25 since 5^2, and a is 9

princeevee · Answer

25 - 9 is 16

princeevee · Answer

so b^2 is 16, i think

princeevee · Answer

but it isnt actually B as of yet, right?

princeevee · Answer

@Hero

Hero · Answer

Nope, because there's still something left to do.

princeevee · Answer

what's that?

princeevee · Answer

subtraction?

Hero · Answer

if $b^2 = 16$ what do you need to do in order to isolate b?

princeevee · Answer

well i just counted in my head for that, and got 4

princeevee · Answer

meaning that cos(theta) is 4/5?

Hero · Answer

Yes correct, but you don't have to count in your head. That takes forever

princeevee · Answer

sorry

princeevee · Answer

think you could help with more?