(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Anglesxandyare located in the first quadrant such that sinx=4/5, and cosy = 7/25.

a) Determine an exact value of cosx.

b) Determine an exact value of siny.

c) Determine an exact value for sin(x+y)

2. Relevant equations

Compound angle formulas perhaps? I don't really know, thats the problem!

3. The attempt at a solution

I'm really at a loss here, do I just sub those in to some formula or something? Can anyone help me out? Or get me pointed in the right direction? thanks in advance!!

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# Given sinx=4/5, cosy = 7/25. Find the following

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