What does “solving” mean?
To solve a quadratic or polynomial means to find the value(s) of xx that make the expression equal zero.
Example:
x^2 – 4 = 0
We are looking for values of xx that make this true.
What is a quadratic?
A quadratic is a polynomial where the highest power of xx is 2.
General form:
ax^2 + bx + c = 0
Quadratics can have:
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Two solutions
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One solution
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No real solutions
What do solutions represent?
Solutions can be:
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x-intercepts of a graph
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Zeros of the function
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Points where the graph crosses the x-axis
All mean the same thing.
Why are there different solving methods?
Because:
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Some quadratics factor easily
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Some do not
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Some are easier to solve visually
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Some require a formula