Let x be the length of one piece and y be the length of the other piece. Then, we can write:
[tex]x+y=60\ldots(A)[/tex]since one piece must be twice long than the other, we can write
[tex]2x=y\ldots(B)[/tex]and we have 2 equations in 2 unknows.
Solving by substitution method.
By substituting equation B into equation A, we get
[tex]x+(2x)=60[/tex]which gives
[tex]\begin{gathered} 3x=60 \\ x=\frac{60}{3} \\ x=20 \end{gathered}[/tex]Now, in order to obtain y, we must substitute this result into equation B. It yields
[tex]\begin{gathered} y=2x\Rightarrow y=2(20) \\ y=40 \end{gathered}[/tex]Therefore, the answer is x= 20 inches and y= 40 inches.