Question

0,6*(4х-18)-0,4*(5-7х) если х=2 1/13

Answer 1

Ответ:

-2

Пошаговое объяснение:

$0,6(4*2\frac{1}{13} -18)-0,4(5-7*2\frac{1}{13} ) = \frac{3}{5} *(4*\frac{27}{13} -18)-\frac{2}{5} *(5-7*\frac{27}{13}) = \frac{3}{5} *(\frac{108}{13} -18)-\frac{2}{5} *(5-\frac{189}{13} ) = \frac{3}{5} * (-\frac{126}{13} ) -\frac{2}{5} * (-\frac{124}{13} )= -\frac{378}{65}+\frac{248}{65} = -\frac{130}{65} =-2$

Answer 2

Ответ:

- 2.

Пошаговое объяснение:

Сначала упростим данное нам выражение:

0,6·(4х-18)-0,4·(5-7х) = 2,4х - 10.8 - 2 + 2,8х = 5,2х - 12,8;

Если х =2 1/13, то

5,2х - 12,8 = 5,2 · 2 1/13 - 12,8 = 26/5 · 27/13 - 12,8 = (26·27)/(5·13) - 12,8 = (2·27)/(5·1) - 12,8 = 54/5 - 12,8 = 10,8 - 12,8 = -2.

Answer 3

To calculate the expression 0.6*(4x-18) - 0.4*(5-7x) when x = 2 1/13, we need to substitute the value of x into the expression and then perform the calculations step by step.

First, let's convert the mixed number x = 2 1/13 into an improper fraction:

x = 2 + 1/13 = (2*13 + 1) / 13 = 27 / 13

Now, substitute x = 27/13 into the expression:

0.6*(4*(27/13) - 18) - 0.4*(5 - 7*(27/13))

Now, perform the calculations:

0.6*(4*(27/13) - 18) = 0.6 * (108/13 - 234/13) = 0.6 * (-126/13) = -75.6/13

And,

0.4*(5 - 7*(27/13)) = 0.4 * (5 - 189/13) = 0.4 * (65/13 - 189/13) = 0.4 * (-124/13) = -49.6/13

Finally, combine the two results:

-75.6/13 - (-49.6/13) = -75.6/13 + 49.6/13 = -26/13 ≈ -2

So, the result of the expression when x = 2 1/13 is approximately -2.