3x=y
X+Y=20
5=x and 15=y are the answer. You can use elimination or substitution or guess and check!
Answer:
The third one. The square in the top left can only fold to the right or down.... which means there is guaranteed to be an open side remaining on the square.
Note this pattern: Mult. 24 by (-1/4) produces -6.
Mult -6 by (-1/4) produces 6/4 = 3/2
Mult. 3/2 by (-1/4) produces 3/8
Looks as though you copied the problem down incorrectly. You wrote 32 for 3/2 and -38 for -3/8.
The common ratio is -1/4.
55 times. All you needed to do was multiply 13 by 4 and then add three.