Select the approximate values of x that are solutions to f(x) = 0, where
f(x) = -5x2 + 7x + 2.

{–0.24, 1.64}

{-5, 7}

{–1.40, –0.40}

{–2.50, 3.50}

Question

Select the approximate values of x that are solutions to f(x) = 0, where
f(x) = -5x2 + 7x + 2.
	
{–0.24, 1.64}
 	
{-5, 7}
 	
{–1.40, –0.40}
 	
{–2.50, 3.50}

anonymous · Answer

what number could you put in for x that would make the output zero

anonymous · Answer

since it is multiple choice you could just plug them into the function

anonymous · Answer

i dont understand the question sorry thats why i asked for some help? can someone please help me with this for i have no idea

myininaya · Answer

you can see which of the pairs get you output closest to 0
are you can use the quadratic formula
and take the approximations form the exact solutions

myininaya · Answer

$$ax^2+bx+c=0 \text{ implies } x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}$$

myininaya · Answer

So first step identify a,b,c

phi · Answer

If you have time, see https://www.khanacademy.org/math/algebra/quadratics/quadratic-formula/v/using-the-quadratic-formula