Question

Help plz. For what value of g does the function f(g) = g2 + 3g equal 18?

Answer 1

the equation is as follow  g2 + 3g =18 it is the same of g2 + 3g -18=0
 we must find the solution

D=3²- 4x1x-18= 9+72=81
the sqrt(81)=9
so g = (-3 - 9 )/ 2= -6
     g= (-3+9)/2=3


the solution is

function f(g) = g2 + 3g equal 18 if g= - 6 or g=3