SOLUTION: Use completing the square to describe the graph of the following function. Support your answer graphically
{{{ f(x)=-2x^2+4x+5 }}}
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Rational-functions
-> SOLUTION: Use completing the square to describe the graph of the following function. Support your answer graphically
{{{ f(x)=-2x^2+4x+5 }}}
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You can put this solution on YOUR website! Use completing the square to describe the graph of the following function. Support your answer graphically
:
-2x^2 + 4x + 5 = 0
coefficient of x^2 has to be 1, divide equation by -2
x^2 - 2x - 2.5 = 0
x^2 - 2x + ___ = 2.5
Complete the square, divide the coefficient of x by 2 and square it
add it to both sides
x^2 - 2x + 1 = 2.5 + 1
x^2 - 2x + 1 = 3.5
which is
(x-1)^2 = 3.5
find the square root of both sides
x - 1 = +/-
Two solutions
x = 1 + approx 2.87
and
x = 1 - approx -.87
:
Graph the original equation, check the x intercepts
