A point on the unit circle is in quadrant 3 and has an x-value of -1/2. What is the y-value of this point?

Sorry guys but as you have a small brain

The average human heart beats 1.15 \cdot 10^51.15⋅10 5 1, point, 15, dot, 10, start superscript, 5, end superscript times per day. there are 3.65 \cdot 10^23.65⋅10 2 3, point, 65, dot, 10, start superscript, 2, end superscript days in one year.how many times does the heart beat in one year? write your answer in scientific notation, and round to one decimal place.

If (x-2) 2= 49, then x could be a. -9 b. -7 c.- 2 d. 5 e.9