X=k*Y
K*Y=X
K=X/Y
K=20/5
K=4
For Y=3/2
X=k*3/2
X=4*3/2
X=6
A point (-0.8, 0.6) will be a point on the unit circle in the second quadrant. Since it is a unit circle, its radius is 1, and we have
sin(α) = y = 0.6
cos(α) = x = -0.8
tan(α) = y/x = 0.6/-0.8 = -0.75
The angle is α = arccos(-0.8) ≈ 143.13°
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For the unit circle, the trig values are always the coordinates or their ratio as shown above, regardless of quadrant.
The amount of work done by Kalon in an hour is equal to 1/4. This is based on his time to finish the job. Letting x be the number of hours Marna can finish the job alone will let her finish 1/x of the job in an hour. If their rates are added together and multiplied by the number of hours they worked together, the product should be one whole job.
(1/4 + 1/x)(1 5/7) = 1
The value of x is 3. Therefore, it will take 3 hours for Marna to clean the chimney alone.
36
List the numbers
31,34,34,35,37,38,38,39
Mark out one from each side till you get 37 and 35 average them to get your answer