Question

-y×(y+7)=(2+y)×(y-2)​

Answer 1

Ответ:

решение смотри на фотографии

Пошаговое объяснение:

Answer 2

Ответ: -4, 0,5

Пошаговое объяснение:

-у×(у+7)=(2+у)×(у-2)

-у^2-7у=2у-4+у^2-2у

-у^2-у^2-7у=-4

-2у^2-7у=-4

-2у^2-7у+4=0

Получилось квадратное уравнение вида ах^2+bx+c=0

Нужно найти дискриминант

D=b^2-4ac

D=(-7)^2-4×(-2)×4

D=49+32=81

D>0, значит уравнение имеет 2 корня

у1= (-b+квадратный корень из D)/2a

y2=(-b-квадратный корень из D)/2a

у1=(-(-7)+9)/2×(-2)

у1=(7+9)/(-4)

у1=16/(-4)

у1=-4

у2=(-(-7)-9)/2×(-2)

у2=(7-9)/(-4)

у2=(-2)/(-4)

у2=1/2 или 0,5

Answer 3

Let's solve the given equation step by step:

-y × (y + 7) = (2 + y) × (y - 2)

Expanding the expressions on both sides:

-y^2 - 7y = (2 + y) × (y - 2)

Now, distribute (2 + y) on the right side:

-y^2 - 7y = y(y - 2) + 2(y - 2)

Simplify further:

-y^2 - 7y = y^2 - 2y + 2y - 4

Combine like terms:

-y^2 - 7y = y^2 - 4

Move all terms to one side of the equation:

-y^2 - 7y - y^2 + 4 = 0

Simplify:

-2y^2 - 7y + 4 = 0

Multiply the entire equation by -1 to simplify further:

2y^2 + 7y - 4 = 0

Now, we can solve this quadratic equation. There are several methods to solve quadratic equations, such as factoring, completing the square, or using the quadratic formula. In this case, let's use the quadratic formula:

For an equation of the form ax^2 + bx + c = 0, the quadratic formula states that the solutions for x are given by:

x = (-b ± sqrt(b^2 - 4ac)) / (2a)

In our equation, a = 2, b = 7, and c = -4. Substituting these values into the quadratic formula:

y = (-7 ± sqrt(7^2 - 4 * 2 * -4)) / (2 * 2)

Simplifying further:

y = (-7 ± sqrt(49 + 32)) / 4 y = (-7 ± sqrt(81)) / 4

y = (-7 ± 9) / 4

This gives two possible solutions:

y = (-7 + 9) / 4 = 2/4 = 1/2

y = (-7 - 9) / 4 = -16/4 = -4

Therefore, the equation has two solutions: y = 1/2 and y = -4.