The farmer should plant 40 trees per acre to maximize her yield to harvest.
<h3>What is a system of equations?</h3>
A system of equations is two or more equations that can be solved to get a unique solution. the power of the equation must be in one degree.
Let F be the number of fruit per acre

Factor out the 3 and complete the square

So the vertex is at (-30, 1200)
70 - 30 = 40
The farmer should plant 40 trees per acre to maximize her yield to harvest.
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