Answer :
when the graph touches x axis at that point y = 0
So, putting y =0
0 = -3x^2 + x +4
so, if you factoriazte it
−3x^2++4x−3x+4=0
−3x(x+1)+4(x+1)=0
(x+1)+(−3x+4)=0
x=−1,4/3
So, two time at -1 and 4/3 it touches the x-axid
So, putting y =0
0 = -3x^2 + x +4
so, if you factoriazte it
−3x^2++4x−3x+4=0
−3x(x+1)+4(x+1)=0
(x+1)+(−3x+4)=0
x=−1,4/3
So, two time at -1 and 4/3 it touches the x-axid