1)
4 ( x -2 ) = 7 x + 9
4x - 8 = 7x + 9
4x - 7x = 9 + 8
-3x = 17
[tex]\bf x=-\dfrac{17}{3}[/tex]
2)
2 ( 2x + 4 ) = 5 ( x + 1)
4x + 8 = 5x + 5
8 - 5 = 5x - 4x
3 = x
x = 3
3)
[tex]\bf \dfrac{x}{2}+5=2x+\dfrac{7}{4}\:\:|\cdot4[/tex]
[tex]\bf 2x+20=8x+7[/tex]
[tex]\bf 20-7=8x -2x[/tex]
[tex]\bf 6x =13[/tex]
[tex]\bf x = \dfrac{13}{6}[/tex]
Răspuns:
1. [tex]-\frac{17}{3}[/tex]
2. 3
3. [tex]-\frac{49}{10}[/tex]
Explicație pas cu pas:
Hey! :)
1. 4 (x-2) = 7x + 9
4x - 8 = 7x + 9
4x - 7x = 9 + 8
-3x = 17
[tex]x = -\frac{17}{3}[/tex]
2. 2 ( 2x + 4 ) = 5 ( x + 1 )
4x + 8 = 5x + 5
4x - 5x = 5 - 8
-x = -3
x = 3
3. [tex]\frac{x}{2+5} = \frac{2x + 7}{4}[/tex]
[tex]\frac{x}{7} = \frac{2x+7}{4}[/tex]
4x = 7 (2x + 7)
4x = 14x + 49
4x - 14x = 49
-10x = 49
[tex]x = -\frac{49}{10}[/tex]