It is b i think hope this helps
Answer:
Step-by-step explanation:
3 i think
Visualize pi/2 as 90° on the unit circle. this has no real component, only imaginary. same for 3pi/2, or -pi/2 as shown in this equation:

as you move around the unit circle, you'll find that 9pi/2 is the same angle as pi/2.
Thus, the rectangular coordinates are:
Answer:
99
Step-by-step explanation:
5x^2 -4x -9
5(-2)^2 -4(-2) -9
-10^2 +8 -9
100-1
99
Answer:
graphing : Find the intersection points
substitution method : If you have e.g. x+2y=9 and x=3+2y, we can substitute it, (3+2y)+2y=9
elimination method : Make two variables the same, minus them and solve the equation
Step-by-step explanation: