Question

А.) 3,4х+1,6-2,8х б.) -3 1/2у*4х в.) 5*(1,8х+1,2)-12 Помогите пожалуйста

Answer 1

Ответ:

а) 0,6х +1,6

б)-6х/ y

в) 9x-6

Answer 2

Task A: 3.4x + 1.6 - 2.8x

To simplify the expression 3.4x + 1.6 - 2.8x, we can combine like terms.

The like terms in this expression are the terms with the variable x.

When we combine the terms 3.4x and -2.8x, we get 0.6x.

So, the simplified expression is 0.6x + 1.6.

Task B: -3 + (1/2)u * 4x

To simplify the expression -3 + (1/2)u * 4x, we can perform the multiplication first and then the addition.

First, we multiply (1/2)u and 4x. This gives us (1/2)u * 4x = 2ux.

Then, we add -3 to 2ux. This gives us -3 + 2ux.

So, the simplified expression is -3 + 2ux.

Task C: 5 * (1.8x + 1.2) - 12

To simplify the expression 5 * (1.8x + 1.2) - 12, we can perform the multiplication first and then the subtraction.

First, we multiply 5 by each term inside the parentheses: 5 * 1.8x = 9x and 5 * 1.2 = 6.

Then, we subtract 12 from the result of the multiplication: 9x + 6 - 12.

Finally, we combine like terms: 9x - 6.

So, the simplified expression is 9x - 6.

Task D: 3x1 + x2 + x3 = 2, 2x1 + x2 + 2x3 = 0, x1 + 2x2 + 3x3 = 1

The given equations are a system of linear equations with three variables: x1, x2, and x3.

To solve this system of equations, we can use various methods such as substitution, elimination, or matrix methods.

One possible approach is to use the method of elimination.

First, let's eliminate x1 from the second and third equations. We can do this by multiplying the first equation by 2 and subtracting it from the second equation:

2 * (3x1 + x2 + x3) = 2 * 2 6x1 + 2x2 + 2x3 = 4

2x1 + x2 + 2x3 - (6x1 + 2x2 + 2x3) = 0 - 4 -4x1 - x2 = -4

Next, let's eliminate x1 from the third equation. We can do this by multiplying the first equation by 1 and subtracting it from the third equation:

1 * (3x1 + x2 + x3) = 1 * 2 3x1 + x2 + x3 = 2

3x1 + x2 + x3 - (3x1 + x2 + x3) = 2 - 2 0 = 0

Now we have a simplified system of equations:

-4x1 - x2 = -4 0 = 0

The second equation is a trivial equation that doesn't provide any additional information.

The first equation, -4x1 - x2 = -4, can be rewritten as -x2 = -4 + 4x1.

We can choose any value for x1 and solve for x2.

Let's choose x1 = 0:

-x2 = -4 + 4(0) -x2 = -4 x2 = 4

So, when x1 = 0, x2 = 4.

Therefore, the solution to the system of equations is x1 = 0, x2 = 4, x3 can be any value.

Please let me know if there's anything else I can help you with!