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How many times does the equation f(x)=2x^2+9x-5 intersect the x-axis

1 Answer

3 votes

Answer:

2

Explanation:

f(x)=2x^2+9x-5

When we are find how many times it intersects the x axis, we are finding the zero's. Set the equation equal to zero

0=2x^2+9x-5

Factor the equation

0 = (2x+1) (x-5)

2*1

1*-5 = -5

2*-5 +1*1 = -9

This checks for the first last and middle terms so we factored correctly

Then using the zero product property

2x+1 = 0 and x-5 =0

2x = -1 x=5

x = -1/2 and x=5

This function crosses the x axis 2 times

User Pickle Rick
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