Question 1028356
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Is sin t equals -4/5 and tan t is negative, what is the value of cos t
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Since sin(t) is negative and tan(t) is negative, the angle t is in fourth quarter.


Then cos(t) = {{{sqrt(1-sin^2(t))}}} = {{{sqrt(1-(-4/5)^2)}}} = {{{sqrt(1-16/25)}}} = {{{sqrt(9/25)}}} = {{{3/5}}}.