Question

7/5(1+3/7×)=×
5/3(2-1/5×)=×
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Answer 1

Răspuns:

$\frac{7}{5}(1+\frac{3x}{7})=x\\ \\\frac{7}{5}+\frac{3x}{5}=x\\ \\7+3x=5x\\\\5x-3x=7\\\\2x=7\\\\x=7/2\\\\\\x=3.5$

$\frac{5}{3}(2-\frac{x}{5})=x\\\\\\\frac{10}{3}-\frac{x}{3}=x\\ \\10-x=3x\\\\3x+x=10\\\\4x=10\\\\x=10/4\\\\x=2.5$

Answer 2

Răspuns:

Explicație pas cu pas:

7/5×(1 + 3x/7) = x

1 + 3x/7 = x : 7/5

1 + 3x/7 = 5x/7  [ × 7 pentru a elimina numitorul

5 x = 7 + 3 x

5 x - 3 x = 7

2 x = 7    ⇒   x = 7/2

Verific:

7/5 × ( 1 + 3/7 × 7/2) = 7/5 × ( 2/2 + 3/2 ) = 7/5 × 5/2 = 7/2 ( x) √

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5/3 ( 2 - 1x/5) = x

⁵⁾2 - x/5 = x : 5/3

10/5 - x/5 = 3 x/5   [ × 5

3 x = 10 - x

3 x + x = 10

4 x = 10

x =( 10/4)⁽²    ⇒ x = 5/2

Verific:

5/3 × ( 2 - 1/5 × 5/2) = 5/3 × ( 4/2 - 1/2) = 5/3 × 3/2 = 5/2 ( x) √