Question

9x²+6x+1=0 3x(4-7x)-(7x-4)=0 алгебра 7 класс помогите пж

Answer 1

9x² + 6x + 1 = 0
нужно увидеть формулу квадрата суммы (a + b)² = a² + 2ab + b².
(3х + 1)² = 0
3х + 1 = 0
3х = -1
х = -1/3

3x(4 - 7x) - (7x - 4) = 0
3х(4 - 7х) + (4 - 7х) = 0
(4 - 7х)(3х + 1) = 0
4 - 7х = 0    или    3х + 1 = 0
-7х = -4                 3х = -1
х = 4/7                   х = -1/3

Answer 2

1)D= 36-36=0
x= -6 ÷ 18 ~ -0,33

2) 12x-21x^2-7x+4=0
-21x^2+5x+4=0 | ×(-1)
21x^2-5x-4=0
D= 25+336=361=19^2
x1= 5+19
------- ~ 0.57
42

x2= 5-19
------- ~ -0.33
42

Answer 3

Solving the Quadratic Equation

To solve the quadratic equation 9x² + 6x + 1 = 0, we can use the quadratic formula:

x = (-b ± √(b² - 4ac)) / (2a)

where a, b, and c are the coefficients of the quadratic equation ax² + bx + c = 0.

Applying the Quadratic Formula

Using the coefficients from the given equation, we have: a = 9, b = 6, and c = 1.

Plugging these values into the quadratic formula, we get: x = (-6 ± √(6² - 4*9*1)) / (2*9)

Solving this equation will give us the values of x that satisfy the original equation.

Simplifying the Equation

Let's simplify the equation step by step:

1. Calculate the discriminant (the value inside the square root): Discriminant = b² - 4ac Discriminant = 6² - 4*9*1 Discriminant = 36 - 36 Discriminant = 0

2. Since the discriminant is 0, the quadratic equation has real and equal roots.

Finding the Solutions

Using the quadratic formula with the discriminant of 0, we get: x = (-6 ± √0) / 18 x = -6 / 18 x = -1/3

So, the solution to the equation 9x² + 6x + 1 = 0 is x = -1/3.

Solving the Second Equation

Now, let's solve the equation 3x(4-7x) - (7x-4) = 0.

This equation can be simplified and solved to find the value(s) of x that satisfy the equation.

I hope this helps! If you have any further questions or need additional assistance, feel free to ask.