Question

Помогите решить уравнение;4(9+7х)+21=393 и 486:(5x+2)=18

Answer 1

4(9+7х)+21=393
36+28х+21=393
28х=393-36-21
28х=336
х=336:28
х=12

486:(5х+2)=18
5х+2=486:18
5х+2=27
5х=27-2
5х=25
х=25:5
х=5

Answer 2

4(9+7х)+21= 393
36 + 24 х + 21 = 393
28х= 393-36-21
28х=336
х=12
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486:(5х+2)=18
5х+2=486:18
5х+2=27
5х=27-2
5х=25
х=5