Răspuns:
[420 - 2 x 45: (37 - 7x)] : (4 x 4 - 1) = 25
[420-90:(37-7x)]:15=25
420-90:(37-7x)=25·15
90:(37-7x)=420-375
37-7x=90:45
7x=37-2
x=35:7
x=5
Răspuns: [tex]\bf \red{\underline{x=5}}[/tex]
Explicație pas cu pas:
[tex]\bf [420 - 2 \cdot 45: (37 - 7x)] : (4 \cdot 4 - 1) = 25[/tex]
[tex]\bf [420 -90: (37 - 7x)] : (16 - 1) = 25[/tex]
[tex]\bf [420 -90: (37 - 7x)] : 15= 25[/tex]
[tex]\bf [420 -90: (37 - 7x)] = 25\cdot 15[/tex]
[tex]\bf 420 -90: (37 - 7x) = 375[/tex]
[tex]\bf 420 =375+90: (37 - 7x)[/tex]
[tex]\bf 420 -375=90: (37 - 7x)[/tex]
[tex]\bf 45=90: (37 - 7x)[/tex]
[tex]\bf 45\cdot (37 - 7x) =90~~~~\bigg|:45[/tex]
[tex]\bf 37 - 7x=2[/tex]
[tex]\bf 37 =2+7x[/tex]
[tex]\bf 37 -2=7x[/tex]
[tex]\bf 35=7x[/tex]
[tex]\bf x = 35 : 7[/tex]
[tex]\bf \red{\underline{x=5}}[/tex]
==pav38==