2: =>y:2=7,94+2,06=10
=>y=20
\(50 , 87 × y + 12 , 09 × y + 37 , 04 × y = 256 + 144\)
\( y × ( 50 , 87 + 12 , 09 + 37 , 04 ) = 400\)
\(y × 100 = 400\)
\(y = 400 : 100 =4\)
Vậy `y=4`
`2` Sửa đề : `y:2=7,94 + 24,72 : 12`
\(y : 2 = 7 , 94 + 27 , 12 : 12\)
\(y : 2 = 7 , 94 + 2 , 06\)
\(y : 2 = 10\)
\(y = 10 × 2\)
`y=20`