Question

0,5x + 1,2 если x=-7 9-5x если x=10,2 (x-4)-(5x-9)=3x-12 5*(3-x)-4*(x+5)=10

Answer 1

Пошаговое объяснение:

1)0.5*(-7)+1.2

-3.5+1.2

-2.3

2)9-5*10.2

9-60

-51

3)x-4-5x+9=3x-12

x-5x-3x=4-9-12

-7x=-12

x=12/7

4)15-5x-4x-20=10

-5x-4x=10-15+20

-9x=15

x=-15/9= -5/3

Answer 2

Let's solve the given equations step by step:

1. For the equation 0.5x + 1.2 when x = -7: Substituting x = -7 into the equation: 0.5(-7) + 1.2 = -3.5 + 1.2 = -2.3

   Therefore, when x = -7, the value of 0.5x + 1.2 is -2.3.

2. For the equation 9 - 5x when x = 10.2: Substituting x = 10.2 into the equation: 9 - 5(10.2) = 9 - 51 = -42

   Therefore, when x = 10.2, the value of 9 - 5x is -42.

3. For the equation (x - 4) - (5x - 9) = 3x - 12: Simplifying the equation: x - 4 - 5x + 9 = 3x - 12 -4x + 5 = 3x - 12

   Moving the variables to one side and the constants to the other side: -4x - 3x = -12 - 5 -7x = -17

   Dividing both sides of the equation by -7: x = -17 / -7 x = 17/7

   Therefore, the solution to the equation (x - 4) - (5x - 9) = 3x - 12 is x = 17/7.

4. For the equation 5*(3 - x) - 4*(x + 5) = 10: Simplifying the equation: 5*(3 - x) - 4*(x + 5) = 10 15 - 5x - 4x - 20 = 10 -9x - 5 = 10

   Moving the constants to the other side: -9x = 10 + 5 -9x = 15

   Dividing both sides of the equation by -9: x = 15 / -9 x = -5/3

   Therefore, the solution to the equation 5*(3 - x) - 4*(x + 5) = 10 is x = -5/3.

To summarize:

• When x = -7, the value of 0.5x + 1.2 is -2.3.
• When x = 10.2, the value of 9 - 5x is -42.
• The solution to the equation (x - 4) - (5x - 9) = 3x - 12 is x = 17/7.
• The solution to the equation 5*(3 - x) - 4*(x + 5) = 10 is x = -5/3.