Explicație pas cu pas:
[tex]\bf a)~ -8x+7=-17[/tex]
[tex]\bf -8x=-17-7[/tex]
[tex]\bf -8x=-24~~~~\bigg|:(-8)[/tex]
[tex]\bf \purple{\underline{~x=3~}}[/tex]
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[tex]\bf b) ~9x-7=7x-15[/tex]
[tex]\bf 9x-7-7x=-15[/tex]
[tex]\bf 2x-7=-15[/tex]
[tex]\bf 2x=-15+7[/tex]
[tex]\bf 2x=-8~~~\bigg|:2[/tex]
[tex]\blue{\underline{~\bf x=-4~}}[/tex]
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[tex]\bf c) ~-63:(5x-4)=7[/tex]
[tex]\bf -63= 7\cdot (5x-4)~~~\bigg|:7[/tex]
[tex]\bf -9= 5x-4[/tex]
[tex]\bf -9+4= 5x[/tex]
[tex]\bf -5= 5x~~~\bigg|:5[/tex]
[tex]\red{\underline{~\bf x=-1~}}[/tex]
