x * 8 +(90 +15 ) = 775
=> x * 8 + 105 = 775
=> x * 8 = 775 - 105
=> x * 8 = 670
=> x = 670 : 8
=> x = 95
x*8+105=775
x*8=775-105
x*8=670
x=670:8
x=83,75
\(x.8+\left(90+15\right)=775\)
\(\Rightarrow x.8+105=775\)
\(\Rightarrow x.8=775-105\)
\(\Rightarrow x.8=670\)
\(\Rightarrow x=670:8\)
\(\Rightarrow x=83,75\)
Dấu \(.\)là nhân
x * 8 + ( 90 + 15 ) = 775
x * 8 + 105 = 775
x * 8 = 775 - 105
x * 8 = 670
x = 670 : 8
x = 83 , 75
\(x.8+\left(90+15\right)=775\)
\(x.8+105=775\)
\(x.8=775-105\)
\(x.8=670\)
\(x=670:8\)
\(x=83,75\)
Chú ý : dấu "." là dấu "x"
x *8+(90+15)=775
x*8+105 =775
x*8 =775-105
x*8 =670
x =670:8
x =83,75.
Đề cử mk nhé!