1 tìm x biết
a ) 100 – 7 9 x-5) = 58
b) 12 ( x – 1 ) . 3 = 4 mũ 3 + 2 mũ 3
c) 5x – 206 = 24.4
d) 24+ 5 x = 7 mũ 5 : 7 mũ 3
1 tìm x biết
a ) 100 – 7 9 x-5) = 58
b) 12 ( x – 1 ) . 3 = 4 mũ 3 + 2 mũ 3
c) 5x – 206 = 24.4
d) 24+ 5 x = 7 mũ 5 : 7 mũ 3
Đáp án:
a ) `100 – 7 ( x-5)= 58 `
`100-7x – 35 =58`
`7x-35=42`
`7x=77`
`7x=77`
`x=11`
b)` 12 ( x – 1 ) * 3 = 4^3 + 2^3`
`12 ( x – 1 ) *3 =72`
`12(x-1)=24`
`x-1=2`
`x=3`
c) `5x – 206 = 24*4`
`5x-206=96`
`5x=302`
`x=302/5`
d) `24+ 5x = 7^5 ÷ 7^3`
`24+5x=49`
`5x=25`
`x=5`
Đáp án:
Giải thích các bước giải:
a ) `100 – 7 (x-5) = 58`
`100-7x+35=58`
`-7x=-77`
`x=11`
b) `12 ( x – 1 ) . 3 = 4^3+2^3`
`36(x-1)=64+8`
`36x-36=72`
`36x=108`
`x=3`
c) `5x – 206 = 24.4`
`5x-206=96`
`5x=302`
`x=64,5`
d) `24+ 5x = 7^5 : 7^3`
`24+5x=7^2`
`5x=25`
`x=5`