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x intercepts(or zeroes) from an equation:

Replace the y variable with a zero, then solve for x. The x values that are the solutions are the x intercepts.  The x intercepts are also called zeroes when the function is a polynomial.

 Quadratic Example(vertex form) Rational Example 
x intercept quadratic vertex form x intercept rational
 Quadratic Example(factored form)
x intercept factored form polynomial
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x intercepts(or zeroes) from a graph:

It's the units value on the x axis where the graphed function intercepts the x axis. The second value if you write it up as a point is always 0.

Polynomial Example:

graph x intercept

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x intercepts on the ti-84

put the equation on the calculator using the y= button

ti x intercept

Find the CALC word and use the 2ND key to access it. Then from the menu select zeroes. The calculator calls x intercepts zeroes.

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Use the arrrow keys to mark the side of the graphed function that is on the left side of the zero and hit ENTER , then mark the graphed function on the right side of the zero and hit ENTER. When the calculator says Guess? hit Enter again. The coordinates of the x intercept will be written on the bottom of the screen.

ti x intercept