Question

решите уравнение 7z-3z =5,12 ; 15*(k-0,2)= 21 срочно!. зарание спасибо))))

Answer 1

1) 7z-3z =5,12 
4z=5.12
z=1.28

2) 15*(k-0,2)= 21
15k-3=21
15k=24
k=1.6

Answer 2

Solving the equation 7z - 3z = 5.12

To solve the equation 7z - 3z = 5.12, we can combine like terms on the left side of the equation:

7z - 3z = 5.12 (7 - 3)z = 5.12 4z = 5.12

To isolate z, we divide both sides of the equation by 4:

4z/4 = 5.12/4 z = 1.28

Therefore, the solution to the equation 7z - 3z = 5.12 is z = 1.28.

Solving the equation 15*(k - 0.2) = 21

To solve the equation 15*(k - 0.2) = 21, we can start by distributing the 15 to the terms inside the parentheses:

15k - 15(0.2) = 21 15k - 3 = 21

Next, we can isolate the variable k by adding 3 to both sides of the equation:

15k - 3 + 3 = 21 + 3 15k = 24

Finally, we divide both sides of the equation by 15 to solve for k:

15k/15 = 24/15 k = 24/15

Simplifying the fraction 24/15, we get:

k = 8/5

Therefore, the solution to the equation 15*(k - 0.2) = 21 is k = 8/5 or k = 1.6.

Please note that the solutions provided are based on the given equations. If there are any additional constraints or information, please let me know, and I'll be happy to assist you further.