Question

Помогите пожалуйста побыстрее решить задачку: 1)0,6*х+7-0,5*х-3=6,8 2)4/9*(2,7м-2ц1/4м)-4,2*(5/7м-0,5n)=? 3)0,3-(x-2)-0,2*(x+4)=0 пожалуйста сделайте побыстрее плыыыззззз =]

Answer 1

0,6*х+7-0,5*х-3=6,8
0,1х+4=6,8
0,1х=6,8-4
х= 2,8/0,1
х=28




0,3-(x-2)-0,2*(x+4)=0
0,3-х+2-0,2х-0,8=0
-1,2х+1,5=0
х=1,5/1,2
х=1,25

Answer 2

1) To solve the equation 0.6x + 7 - 0.5x - 3 = 6.8, we can simplify the equation and solve for x.

First, let's simplify the equation: 0.6x - 0.5x + 7 - 3 = 6.8 0.1x + 4 = 6.8

Next, let's isolate the variable x by subtracting 4 from both sides of the equation: 0.1x = 6.8 - 4 0.1x = 2.8

Finally, divide both sides of the equation by 0.1 to solve for x: x = 2.8 / 0.1 x = 28

Therefore, the solution to the equation 0.6x + 7 - 0.5x - 3 = 6.8 is x = 28.

2) To solve the expression 4/9 * (2.7m - 2c1/4m) - 4.2 * (5/7m - 0.5n), we can simplify the expression and perform the calculations.

First, let's simplify the expression: 4/9 * (2.7m - 2c1/4m) - 4.2 * (5/7m - 0.5n)

Next, let's simplify each term separately: 4/9 * (2.7m - 2c1/4m) = (4/9) * (2.7m) - (4/9) * (2c1/4m) = (4/9) * 2.7m - (4/9) * (2 + 1/4)m = (4/9) * 2.7m - (4/9) * (9/4)m = (4/9) * 2.7m - (1/1) * (1/1)m = (4/9) * 2.7m - m = (4/9) * 2.7 - 1m = 1.2m - m = 0.2m

Similarly, let's simplify the second term: 4.2 * (5/7m - 0.5n) = 4.2 * (5/7m) - 4.2 * 0.5n = (4.2 * 5/7)m - 2.1n = 3m - 2.1n

Now, let's substitute the simplified terms back into the original expression: 4/9 * (2.7m - 2c1/4m) - 4.2 * (5/7m - 0.5n) = 0.2m - (3m - 2.1n) = 0.2m - 3m + 2.1n = -2.8m + 2.1n

Therefore, the simplified expression 4/9 * (2.7m - 2c1/4m) - 4.2 * (5/7m - 0.5n) is -2.8m + 2.1n.

3) To solve the equation 0.3 - (x - 2) - 0.2 * (x + 4) = 0, we can simplify the equation and solve for x.

First, let's simplify the equation: 0.3 - (x - 2) - 0.2 * (x + 4) = 0 0.3 - x + 2 - 0.2x - 0.8 = 0 2.5 - 1.2x = 0

Next, let's isolate the variable x by subtracting 2.5 from both sides of the equation: -1.2x = -2.5

Finally, divide both sides of the equation by -1.2 to solve for x: x = -2.5 / -1.2 x = 2.0833 (rounded to four decimal places)

Therefore, the solution to the equation 0.3 - (x - 2) - 0.2 * (x + 4) = 0 is x ≈ 2.0833.