MHB Finding the Minimum Value of a Parabola: Tips and Techniques

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To find the minimum value of the quadratic function f(x)=3x^2+10x+219, the vertex formula x=-b/(2a) can be used, where a=3 and b=10. Calculating this gives x=-10/(2*3)=-5/3. Substituting x back into the function provides the minimum value of f(x). Additionally, participants are reminded to adhere to forum rules, particularly regarding clarity in expressing difficulties. Understanding the vertex's role is crucial for solving problems involving parabolas.
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What is the smallest value in the image set of the function:

f(x)=3x^2+10x+219
 
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The vertex (minimum or maximum) of a parabola $f(x)=ax^2+bx+c$ has $x$-coordinate $x=-\dfrac{b}{2a}$.

For the future, please read the forum http://mathhelpboards.com/rules/, especially rule #11. In this case, you could write what facts about parabolas you know and what exactly your difficulty is in applying them.
 
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