Wire fence

The wire fence around the garden is 160 m long. One side of the garden is three times longer than the other. How many meters do the individual sides of the garden measure?

Final Answer:

a =  60 m
b =  20 m

Step-by-step explanation:

$$\begin{gathered} 2(a+b)=160 \\ a=3b \\ 2\cdot (a+b)=160 \\ a=3\cdot b \\ 2a+2b=160 \\ a-3b=0 \\ Row2-\frac{1}{2}\cdot Row1\to Row2 \\ 2a+2b=160 \\ -4b=-80 \\ b=\frac{-80}{-4}=20 \\ a=\frac{160-2b}{2}=\frac{160-2\cdot 20}{2}=60 \\ a=60 \\ b=20 \end{gathered}$$

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