I need to find the approx. value for x that are solutions to f(x)=0 for

f(x)=-5x^2 + 7x + 2

please show steps as the answer I got does not match any of the multiple choices.

since you show neither your work nor the choices, it's tough to see where you went wrong.

However, the roots will be equidistant from the axis of symmetry, at

x = 7/10 = 0.7

So, pick the choice where the roots are the same amount above and below 0.7