Question

F(x)= 3x^2+5x-8. Solve the quadratic equation

Answer 1

Answer:

             $\bold{x_1=1\ ,\quad x_2=-\dfrac83}$

Step-by-step explanation:

$3x^2+5x-8=0\quad\implies\quad a=3\,,\ b=5\,,\ c=-8\\\\x=\dfrac{-5\pm\sqrt{5^2-4(3)(-8)}}{2\cdot3}=\dfrac{-5\pm\sqrt{25+96}}{6}=\dfrac{-5\pm\sqrt{121}}{6}\\\\ x_1=\dfrac{-5+11}{6}=1\ ,\qquad x_2=\dfrac{-5-11}{6}=\dfrac{-16}6=-\dfrac83$