Question

1)5(х+8,4) -(3х+30) = 0 2) 3х-2/8=5/4

Answer 1

Ответ:

1) - 6;   2) 0,5.

Пошаговое объяснение:

Решить уравнения:

1) 5(х+8,4) -(3х+30)=0

2) 3х -2/8= 5/4

1) Раскроем скобки, применяя распределительное свойство умножения относительно сложения a · (b +c) =a · b + a · c  и правило раскрытия скобок, если перед ними стоит знак " -" .

5(х+8,4) -(3х+30)=0;

5· x + 5· 8,4 - 3x - 30 =0;

5x + 42 - 3x - 30=0;

2x + 12 =0;

2x = - 12;

x = - 12 : 2;

x= - 6

2) Умножим обе части уравнения на 8

$3x- \dfrac{2}{8} = \dfrac{5}{4} |\cdot 8;\\\\3x^{\backslash8}- \dfrac{2}{8}^{\backslash1} = \dfrac{5}{4}^{\backslash2};\\\\24x - 2= 10;\\\\24x=10+2;\\\\24x=12;\\\\x= 12:24;\\\\x= 0,5$

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Answer 2

Let's solve each equation step by step:

1. 5(x + 8.4) - (3x + 30) = 0

First, distribute the 5 on the left side of the equation:

5x + 42 - (3x + 30) = 0

Now, remove the parentheses:

5x + 42 - 3x - 30 = 0

Combine like terms:

(5x - 3x) + (42 - 30) = 0

2x + 12 = 0

Now, isolate the variable x:

2x = -12

Divide both sides by 2:

x = -12 / 2

x = -6

So, the solution to the first equation is x = -6.

2. 3x - 2/8 = 5/4

First, simplify the fraction on the left side by dividing both the numerator and denominator by 2:

3x - 1/4 = 5/4

Now, add 1/4 to both sides of the equation to isolate the term with x:

3x = 5/4 + 1/4

3x = 6/4

Now, simplify the right side:

3x = 3/2

Finally, divide both sides by 3 to solve for x:

x = (3/2) / 3

x = (1/2) / 3

x = 1/6

So, the solution to the second equation is x = 1/6.