Explicație pas cu pas:
5. a+b=38
a-b=8 => a=b+8
b+8+b=38
2b+8=38
2b=38-8
2b=30
b=30:2
b=15
a=b+8
a=15+8
a=23
6. 3(2x-5)+13=2(x+4)+7
6x-15+13=2x+8+7
6x-2=2x+15
6x-2x=15+17
4x=32
x=8
7. 7(2x-1)-3(4x-1)=5(3x+2)-1
14x-7-12x+3=15x+10-1
2x-4=15x+9
2x-15x=9+4
- 13x=13
x=-1
8.
[tex]2 \frac{2}{3} + 5x = 3x - 1 \frac{2}{6} [/tex]
[tex] \frac{2 \times 3 + 2}{3} + 5x = 3x - \frac{1 \times 6 + 2}{6} [/tex]
[tex] \frac{8}{3} + 5x = 3x - \frac{8}{6} [/tex]
[tex] \frac{16}{6} + \frac{30x}{6} = \frac{18x}{6} - \frac{8}{6} [/tex]
16+30x=18x-8
16+8=18x-30x
24=-12x
x=-2
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Sper că te-am ajutat!
