Equation of parabola is y2=−4x ∴ focus is (−1,0). The equation of line passing through (−1,0) is y−0=m(x+1) .......(i) Since, the line makes an angle θ=120° ∴m=tan‌θ=tan‌120° ⇒m=−√3 On putting the value of m in Eq. (i), we get y=−√3(x+1)