Question 195245
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Is there some reason that you feel the need to shout?  Typing in all CAPS is the  electronic equivalent of shouting and is both rude and annoying.



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Use the quadratic formula to determine the roots of


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ -x^2 + 4x + 1 = 0]


The two x-intercepts will be the points *[tex \Large (x_1,0)] and *[tex \Large (x_2,0)] where *[tex \Large x_1] and *[tex \Large x_2] are the roots of the equation.


Substitute 0 for x and do the arithmetic to calculate the value of the y-coordinate of the y-intercept.  The y-intercept will be the point *[tex \Large (0,y)] where y is the y-coordinate value you just calculated.


The vertex of a parabola whose equation is:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ y = ax^2 + bx + c]


has an x-coordinate equal to *[tex \LARGE \frac{-b}{2a}].  Once you calculate this x-coordinate value, substitute that value for x in the equation and do the arithmetic to calculate the y-coordinate of the vertex.



John
*[tex \LARGE e^{i\pi} + 1 = 0]
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