the answer is c.
you have to multiply by -3 on both sides to get c on its own.
therefore, c is greater than or equal to -9.
in a, c is less than or equal to 9 so thats not the answer.
In b, c is greater than or equal to 9 but it has to be -9.
in d, c is less than or equal to -9.
the answer is c
Answer:
Step-by-step explanation:
Firstly, note that -2i really is just z = 0 + (-2)i, so we see that Re(z) = 0 and Im(z) = -2.
When we're going from Cartesian to polar coordinates, we need to be aware of a few things! With Cartesian coordinates, we are dealing explicitly with x = blah and y = blah. With polar coordinates, we are looking at the same plane but with angle and magnitude in consideration.
Graphing z = -2i on the Argand diagram will look like a segment of the y axis. So we ask ourselves "What angle does this make with the positive x axis? One answer you could ask yourself is -90°! But at the same time, it's 270°! Why do you think this is the case?
What about the magnitude? How far is "-2i" stretched from the typical "i". And the answer is -2! Well... really it gets stretched by a factor of 2 but in the negative direction!
Putting all of this together gives us:
z = |mag|*(cos(angle) + isin(angle))
= 2*cos(270°) + isin(270°)).
To verify, let's consider what cos(270°) and sin(270°) are.
If you graph cos(x) and look at 270°, you get 0.
If you graph sin(x) and look at 270°, you get -1.
So 2*(cos(270°) + isin(270°)) = 2(0 + -1*i) = -2i as expected.
Answer:
16
Step-by-step explanation:
do the parentheses first to get 4
8/2 x 4
4 x 4
16
<span>Y DO I W? (Why do I double you?)
That's the answer. </span>
A= l*w
168= 14*w
Divide both sides by 14
168/14= 14w/14
12=w
Final answer: 12 ft (I'm not sure if you meant to switch the order of b and c).