Question

2/3/4/9x-4/9+1/20=4/5

Answer 1

Пошаговое объяснение:

2/3 : ( 4х/9-4/9)+1/20=4/5

2/3: (4/9(х-1))=4/5-1/20

(2/3*9/4):(х-1)=15/20

3/2* 1/(х-1)=3/4

1/(х-1)=3/4 *2/3

1/(х-1)=1/2

х-1=2

х=3

проверка:

2/3 : ( 4/9 * 3 - 4/9)+1/20=4/5

2/3: 8/9 +1/20=4/5

2/3*9/8+1/20=4/5

3/4+1/20=4/5

16/20=4/5

4/5=4/5

верно

Answer 2

To solve the equation (2/3) / (4/9) + (1/20) = 4/5, we need to simplify the expression on the left-hand side step by step.

Step 1: Simplify (2/3) / (4/9): To divide fractions, we multiply the first fraction by the reciprocal of the second fraction: (2/3) * (9/4) = (2 * 9) / (3 * 4) = 18/12 = 3/2.

So, the equation becomes: (3/2) + (1/20) = 4/5.

Step 2: Find a common denominator for (3/2) and (1/20): The least common multiple of 2 and 20 is 20. We can rewrite (3/2) as (30/20) to have the same denominator.

So, the equation becomes: (30/20) + (1/20) = 4/5.

Step 3: Add the fractions with the same denominator: (30/20) + (1/20) = (30 + 1) / 20 = 31/20.

Now, the equation becomes: 31/20 = 4/5.

Step 4: Cross-multiply to solve for the unknown: Cross-multiplying means multiplying the numerator of the first fraction by the denominator of the second fraction and vice versa.

4 * 20 = 5 * 31, 80 = 155.

Since 80 is not equal to 155, the equation is not true. Therefore, there is no solution to the equation (2/3) / (4/9) + (1/20) = 4/5.