Question

PLEASE help me with these and explain how you get the answer :)

Answer 1

For each question you want to isolate for the variable. It is important to remember that what you do to one side of the equation, you must do to the other. You isolate by preforming the opposite function. So to isolate where there is addition, you would subtract and vice versa. All of these equations are done with multiplication so you undo or isolate them by division. 7 is asking what you multiply (-1/4) by to get (1/18). To isolate for p, you need to divide by (-1/4). (1/18)/(-1/4)=(-2/9). You can check your work by substituting your answer back into the equation. (-1/4)(-2/9)=(1/18). Therefore, p = (-2/9)

8 is the same. To isolate for w, you need to divide by (11/-12). -1/(11/-12)=(12/11).
W = (12/11). Again you can double check by substituting your answer back into the equation where your variable once was.

9 tries to trick you by making the equation equal to 0. The same method used for 7 and 8 will work here as well. You could also solve by knowing that anything multiplied by 0 is equal to 0. So x = 0.

In order to have both sides of the equation look the same in 10, you want to multiply 2 by 9 = 18, and then add 2. After doing this, your equation looks like (2/3)m = (20/9). You then want to isolate for m by dividing (20/9) by (2/3).
(20/9)/(2/3)=(10/3).
Therefore, m = (10/3)