[tex]ax^2+bx+c=0\\\\x_1,\ x_2-solutions\\\\x_1+x_2=\dfrac{-b}{a}\\--------------------------\\\\4x^2-7x-2=0\\\\a=4,\ b=-7,\ c=-2\\\\p,\ q-solutions\\\\p+q=\dfrac{-(-7)}{4}=\dfrac{7}{4}[/tex]