Question

(2,1+0,3y)(7y-4,2)=0​

Answer 1

Ответ:

y1= -7, y2=3\5(0,6)

Объяснение:

(2,1+0,3y)(7y-4,2)=0​

(21\10+3\10y)(7y-21\5)=0

Тк последнее действие умножение, то каждую скобку мы можем приравнять к 0

(21\10+3\10y)=0                                     (7y-21\5)=0

обе части умножаем на 10              7у=21\5

21+3у=0                                               разделить обе стороны на 7

3у=-21                                                  у=3\5 (0,6)

у=-7

Answer 2

To solve the equation (2,1+0,3y)(7y-4,2) = 0, you'll need to find the values of y that make the equation true. To do this, you can expand and simplify the expression:

(2,1+0,3y)(7y-4,2) = 0

First, distribute the terms:

(2 * 7y - 2 * 4,2 + (0,3y * 7y) - (0,3y * 4,2)) = 0

Now, perform the multiplications and simplifications:

(14y - 8,2 + 0,3y^2 - 1,26y) = 0

Combine like terms:

(14y - 1,26y + 0,3y^2 - 8,2) = 0

Now, combine the y-terms:

(14y - 1,26y) + 0,3y^2 - 8,2 = 0

(12,74y) + 0,3y^2 - 8,2 = 0

Now, combine the constants:

12,74y - 8,2 + 0,3y^2 = 0

Rearrange the equation and set it equal to 0:

0,3y^2 + 12,74y - 8,2 = 0

Now, you have a quadratic equation. To solve for y, you can use the quadratic formula:

y = (-b ± √(b² - 4ac)) / (2a)

In this equation, a = 0.3, b = 12.74, and c = -8.2. Plug these values into the formula:

y = (-12.74 ± √(12.74² - 4 * 0.3 * (-8.2))) / (2 * 0.3)

Now, calculate the values of y:

y = (-12.74 ± √(162.3076 + 9.84)) / 0.6

y = (-12.74 ± √(172.1476)) / 0.6

y = (-12.74 ± 13.11) / 0.6

Now, calculate the two possible solutions for y:

1. y = (-12.74 + 13.11) / 0.6 = 0.78333
2. y = (-12.74 - 13.11) / 0.6 = -41.85

So, the two solutions for the equation (2,1+0,3y)(7y-4,2) = 0 are y = 0.78333 and y = -41.85.