Which are the solutions of the quadratic equation?

x2 = 7x + 4

StartFraction negative 7 minus StartRoot 65 EndRoot Over 2 EndFraction comma StartFraction negative 7 + StartRoot 65 EndRoot Over 2 EndFraction
–7, 0
StartFraction 7 minus StartRoot 65 EndRoot Over 2 EndFraction comma StartFraction 7 + StartRoot 65 EndRoot Over 2 EndFraction
7, 0

Respuesta :

Answer:

[tex]x_1=\frac{7+\sqrt{65}} {2}[/tex]

[tex]x_2=\frac{7-\sqrt{65}} {2}[/tex]

Step-by-step explanation:

we know that

The formula to solve a quadratic equation of the form

[tex]ax^{2} +bx+c=0[/tex]

is equal to

[tex]x=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}[/tex]

in this problem we have

[tex]x^{2}=7x+4[/tex]  

equate to zero

[tex]x^{2}-7x-4=0[/tex]  

so

[tex]a=1\\b=-7\\c=-4[/tex]

substitute in the formula

[tex]x=\frac{-(-7)\pm\sqrt{-7^{2}-4(1)(-4)}} {2(1)}[/tex]

[tex]x=\frac{7\pm\sqrt{65}} {2}[/tex]

therefore

[tex]x_1=\frac{7+\sqrt{65}} {2}[/tex]

[tex]x_2=\frac{7-\sqrt{65}} {2}[/tex]

StartFraction 7 minus StartRoot 65 EndRoot Over 2 EndFraction comma StartFraction 7 + StartRoot 65 EndRoot Over 2 EndFraction

Answer: the answer is C.

Step-by-step explanation:got it right

ACCESS MORE