Question

1)(х-2,5)*4 1/5=6,3 ;2)3,5*(х+2 1/4)=14;3) (1 3/4+x): 1,9=2,5;(7,1-x):3,6=1 1/2.

Answer 1

2) 3,5(х+2 1/4)=14
3,5х+8,75=14
3,5х=5,25
х=2/3

Answer 2

To solve each of these equations, we will perform the required operations step by step. Let's go through each one:

1. (х-2.5)*4 1/5 = 6.3

Step 1: Convert 4 1/5 to an improper fraction. 4 1/5 = 4 + 1/5 = 21/5

Step 2: Distribute the multiplication on the left side of the equation. 4 1/5 * (x - 2.5) = 6.3 (21/5) * (x - 2.5) = 6.3

Step 3: Solve for x. 21/5 * x - 21/5 * 2.5 = 6.3 21x/5 - 21/2 = 6.3 21x/5 = 6.3 + 21/2 21x/5 = 6.3 + 10.5 21x/5 = 16.8

Step 4: Divide both sides by 21/5 to isolate x. x = 16.8 / (21/5) x = 16.8 * (5/21) x = 0.8

So the solution to the equation is x = 0.8.

2. 3.5 * (х + 2 1/4) = 14

Step 1: Convert 2 1/4 to an improper fraction. 2 1/4 = 2 + 1/4 = 9/4

Step 2: Distribute the multiplication on the left side of the equation. 3.5 * (x + 9/4) = 14

Step 3: Solve for x. 3.5x + 3.5 * 9/4 = 14 3.5x + 31.5/4 = 14

Step 4: Move the constant term to the other side of the equation. 3.5x = 14 - 31.5/4 3.5x = 56/4 - 31.5/4 3.5x = (56 - 31.5)/4 3.5x = 24.5/4

Step 5: Divide both sides by 3.5 to isolate x. x = (24.5/4) / 3.5 x = 24.5/4 * 1/3.5 x = 24.5/14 x ≈ 1.75

So the solution to the equation is x ≈ 1.75.

3. (1 3/4 + x) / 1.9 = 2.5

Step 1: Convert 1 3/4 to an improper fraction. 1 3/4 = 1 + 3/4 = 7/4

Step 2: Multiply both sides by 1.9 to get rid of the fraction in the denominator. 1.9 * (1 3/4 + x) = 2.5 * 1.9 1.9 * (7/4 + x) = 4.75

Step 3: Distribute the multiplication on the left side of the equation. 1.9 * 7/4 + 1.9 * x = 4.75

Step 4: Solve for x. 1.9x = 4.75 - 1.9 * 7/4 1.9x = 4.75 - 1.9 * 1.75 1.9x = 4.75 - 3.325 1.9x = 1.425

Step 5: Divide both sides by 1.9 to isolate x. x = 1.425 / 1.9 x ≈ 0.75

So the solution to the equation is x ≈ 0.75.

4. (7.1 - x) / 3.6 = 1 1/2

Step 1: Convert 1 1/2 to an improper fraction. 1 1/2 = 1 + 1/2 = 3/2

Step 2: Multiply both sides by 3.6 to get rid of the fraction in the denominator. 3.6 * (7.1 - x) = 3.6 * (3/2) 25.56 - 3.6x = 5.4

Step 3: Move the constant term to the other side of the equation. 3.6x = 25.56 - 5.4 3.6x = 20.16

Step 4: Divide both sides by 3.6 to isolate x. x = 20.16 / 3.6 x = 5.6

So the solution to the equation is x = 5.6.