Question

Which are the solutions of the quadratic equation?

x2=7X+4
-7-165 -7 + 165
-7.0
7- 165 7+ / 65
7,0

Answer 1

(C)

Explanation:

♥☺

Answer 2

For this case we must find the roots of the following equation:

`x ^ 2-7x-4 = 0`

We have to:

`x = \frac {-b \pm \sqrt {b ^ 2-4 (a) (c)}} {2 (a)}`

Where:

`a = 1\\b = -7\\c = -4`

Substituting the values:

`x = \frac {- (- 7) \pm \sqrt {(- 7) ^ 2-4 (1) (- 4)}} {2 (1)}\\x = \frac {7 \pm \sqrt {49 + 16}} {2}\\x = \frac {7\pm\sqrt {65}} {2}`

We have two roots:

`x_ {1} = \frac {7+ \sqrt {65}} {2} = 7.53\\x_ {2} = \frac {7- \sqrt {65}} {2} = - 0.53`

Answer:

`x_ {1} = \frac {7+ \sqrt {65}} {2} = 7.53\\x_ {2} = \frac {7- \sqrt {65}} {2} = - 0.53`