Digital SAT Math Test 2 Question 8

In an isosceles triangle $ABC$, $cos(A)=\frac{12}{13}$ and $cos(B)=-0.70$. What is the value of $sin(C)$ in simplified fraction?
Answer:
Answer:
5/13

Explanation

The correct answer is $\frac{5}{13}$

Draw a diagram for the right-angled triangle as described in the question and then find $sin(C)$.

✨ Expert's Tip ✨

An angle is greater than $90°$ and less than $270°$ when the cosine of the angle is negative, based on unit circle trigonometry.

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