Answer:
<h2>D. Quadrant III</h2>
Step-by-step explanation:
Quadrant in coordinate geometry is divided into four parts which is called Quadrants.
Quadrants I (x, y)
Quadrants II (-x, y)
Quadrants III (-x, -y)
Quadrants IV (x, -y)
so W(-3, -9) both are negatives so its lie on Quadrants III
According to google, the red marks mean those two lines are the same length. If that's the case, we know that x is the angle in both corners of the lower triangle. We also know that because the angle of a straight line is 180, that the top angle of the bottom triangle is 140, because it's divided into two parts, one of which is 40. That leaves 140 for the rest. Now we know that there are 180 degrees in a triangle so x=(180-140)/2 = x=20degrees.
The right angle in the left corner is 90 degrees. It is divided in two parts, the lower one of which we just found to be 20. So the other part must by 70deg.
So for the upper angle y, we have 180-70-40= y=70degrees
Cos(theta) has positive values in quadrants I and IV and it has negative value in quadrants II and III. To know that you don't have to remember this but to imagine xy coordinate system. In it you draw a circle around the center.
Once you do that for any given angle you project the point which represents crossing of side that defines angle and circle. Now project that dot on x-axis. If projection is on positive side of x-axis, cos of that angle is positive and if it is on negative side it is negative.
The correct answer is:
B: 48
Hope this helped!
