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Writing Systems of Equations from Word ProblemsPetri planted two trees. The first was 3 feet tall whenplanted and grows 0.25 feet each month.The second, he planted as a seed 1 foot underground,and it grows 0.5 feet each month. When will the treesbe the same height?Oy = 0.25x + 3 Oy = 0.25x + 3y = 0.5x + 1y = 0.5x - 1Oy = 3x + 0.25Oy = 0.25x + 3y = -1x + 0.5y = -0.5x - 1

User LarrikJ
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1 Answer

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21 votes

The equation for tree 1 and tree 2 would be


\begin{gathered} y=0.25x+3 \\ y=0.5x-1 \\ \text{They would be the same height when,} \\ 0.25x+3=0.5x-1 \\ 3+1=0.5x-0.25x \\ 4=0.25x \\ x=(4)/(0.25)=16\text{ months} \end{gathered}

Then they would be both


0.25(16)+3=4+3=7\text{ f}eet

User Jon Claus
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