Question

X^2-8x+7=0 Решите ) ))))

Answer 1

X²-8x+7=0
D=b²-4ac=(-8)²-4*1*7=64-28=36
x1=(-b+√D)/2a=(-(-8)+6)/2*1=(8+6)/2=7
x2=(-b-√D)/2a=(-8)-6)/2*1=(-14)/2=-7
Ответ: х=7

Answer 2

To solve the quadratic equation $x^2 - 8x + 7 = 0$, we can use the quadratic formula:

The quadratic formula is given by: $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$

Where $a$, $b$, and $c$ are the coefficients of the quadratic equation $ax^2 + bx + c = 0$.

In our case, $a = 1$, $b = -8$, and $c = 7$, so we can plug these values into the formula:

$x = \frac{-(-8) \pm \sqrt{(-8)^2 - 4 \cdot 1 \cdot 7}}{2 \cdot 1}$

$x = \frac{8 \pm \sqrt{64 - 28}}{2}$

$x = \frac{8 \pm \sqrt{36}}{2}$

$x = \frac{8 \pm 6}{2}$

Now, we have two possible solutions:

1. $x = \frac{8 + 6}{2} = \frac{14}{2} = 7$

2. $x = \frac{8 - 6}{2} = \frac{2}{2} = 1$

So the solutions to the equation are $x = 7$ and $x = 1$.