7x + 5 =705
7x =705 - 5 =700
x= 700 : 7 =100
3x+4x+5=705
=>3x+4x=705-5
=>(3+4).x=700
=>7x=700
=>x=700:7
=>x=100
3x+4x+5= 705
=> 7x + 5 = 705
=> 7x = 705 - 5
=> 7x = 700
=> x = 700 : 7
=> x = 100
3x+4x+5=705
=> x.(3+4)=705-5
x . 7 = 700
x = 700:7
x = 100
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