Question

Wich are the solutions of X2 = -5x + 8

Answer 1

Answer:

$x = \frac{-5+/-\sqrt{57} }{2}$

Step-by-step explanation:

To solve the quadratic equation, rearrange it into $ax^2+bx+c$.

$x^2=-5x+8\\x^2 + 5x-8$

This quadratic is not factorable and to solve needs the quadratic formula.

The quadratic formula is $x=\frac{-b+/-\sqrt{b^2-4ac} }{2a}$. Here a=1, b=5, and c=-8.

Substitute and you'll have:

$x=\frac{-b+/-\sqrt{b^2-4ac} }{2a} =\frac{-5+/-\sqrt{5^2-4(1)(-8)} }{2(1)}=\frac{-5+/-\sqrt{25+32} }{2)}$

$\frac{-5+/-\sqrt{57} }{2}$