Question

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

Answer 1

Answer:

2

Step-by-step 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