Bar cutting ratio

The 180 cm long bar should be cut into two parts so that the longer part is 4 cm shorter than three times, the shorter part. Find the lengths of the resulting bar sections.

Final Answer:

a =  134 cm
b =  46 cm

Step-by-step explanation:

$$\begin{gathered} a+b=180 \\ a=3b-4 \\ a=3\cdot b-4 \\ a+b=180 \\ a-3b=-4 \\ Row2-Row1\to Row2 \\ -4b=-184 \\ b=\frac{-184}{-4}=46 \\ a=180-b=180-46=134 \\ a=134 \\ b=46 \end{gathered}$$

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