Question

9х²-81=0решите уравнение​

Answer 1

Ответ:

х₁ = 3; х₂ = -3

Объяснение:

9х² - 81 = 0

9х² = 81

х² = 9

х₁ = 3

х₂ = -3

Answer 2

Ответ:х=3 х=-3

Объяснение:9х²-81=0. ( 3 -х)(3+х)=0 3-х=0 х=3 и 3+х=0 х=-3

Answer 3

To solve the equation 9x² - 81 = 0, we can use the factoring method. Here's how:

Step 1: Rewrite the equation in the form of a quadratic equation: ax² + bx + c = 0. The given equation is already in this form.

Step 2: Factor out the common factor, if possible. In this case, we can factor out a common factor of 9: 9(x² - 9) = 0

Step 3: Recognize the difference of squares pattern. The expression inside the parentheses, x² - 9, can be factored using the difference of squares formula: a² - b² = (a + b)(a - b). In this case, a = x and b = 3: (x + 3)(x - 3) = 0

Step 4: Set each factor equal to zero and solve for x. Setting (x + 3) equal to zero: x + 3 = 0 x = -3

Setting (x - 3) equal to zero: x - 3 = 0 x = 3

Therefore, the solutions to the equation 9x² - 81 = 0 are x = -3 and x = 3.