Answer:
x = 15
Step-by-step explanation:
I am going to use the "butterfly" method for proportions
(there is another type of butterfly method that is different, I am not sure if there is another name for this method, sorry!)
Multiply the:
- top left by the bottom right
-the top right by the bottom left
and then:
- set them equal to each other
So we will <u>multiply 7 by x and 21 by 5</u> (if this doesn't make sense tell me and I will explain it even more!)
7x = 21 * 5
7x = 105
(Divide both sides by 7) <em>x = 15</em>
Hope this helps, have a nice day! :D <3