Question #aab2d

1 Answer
Sep 11, 2016

7+21+39 = 67 " inches"7+21+39=67 inches

Explanation:

All the lengths are described in terms of the first piece, so let's define that as the variable.

Let the length of the first piece be xx

1st piece: xx
2nd piece: 3x3x
3rd piece: 5x +45x+4

All 3 pieces together make 67 inches, write an equation to show this

x+3x+5x+4 = 67x+3x+5x+4=67

9x +4 = 679x+4=67

9x +4 - 4 = 67 - 49x+44=674

9x = 639x=63

x = 7x=7

Go back to the original definitions of the lengths:

1st piece: x = 7 " inches"x=7 inches
2nd piece: 3x = 3xx 7 = 21 " inches"3x=3×7=21 inches
3rd piece: 5x +4 = 5xx7+4 = 39 "inches"5x+4=5×7+4=39inches

Check: 7+21+39 = 67 " inches"7+21+39=67 inches