I think you mean to say

. If

is in the third quadrant, then

and

. Recall that

We expect

to be negative, so we take the negative root. We end up with

We also know to expect

, so

By definition, we have

and so
A) To solve this equation, you would need to fill in the blank with a substitute. Let x represent the unknown number.

=

Next, you would cross multiply.
135 = 45x
Now, the last step would be to isolate the x. To do this, you would divide both sides by 45.
3 = x
= 
b) To solve this equation, you would need to fill in the blank with a substitute. Let x represent the unknown number.

=

Next, you would cross multiply.
18 = 2x
Now, the last step would be to isolate the x. To do this, you would divide both sides by 2.
9 = x
=
I hope this helps!
The answer would be (C).
To be fully simplified, the numerator and denominator must have a GCF of 1.
Answer (C) says 3/57. However, using the divisibility rule of 3 (add the digits together, and if the sum is a multiple of 3, then the number is as well), we see that 57 is divisible by 3, meaning this fraction is not simplified. The simplified version would be 1/19.
<h3><u>The value of x is equal to -2.</u></h3>
5(2x + 8) = -8x + 4
<em><u>Distributive property.</u></em>
10x + 40 = -8x + 4
<em><u>Add 8x to both sides.</u></em>
18x + 40 = 4
<em><u>Subtract 40 from both sides.</u></em>
18x = -36
<em><u>Divide both sides by 18</u></em>
x = -2