a)13,2 - x = -4,3
=> x = 13,2 - ( -4,3)
=> x = 17,5
b)x phần 3 = 20 phần 15
\(\dfrac{x}{3}=\dfrac{20}{15}=>20.3=x.15=>60=x.15=>x=60:15=>x=4\)
c) 2 phần 3 - 1 phần 3 x = -5 phần 3 + 1 phần 2
Mong bạn viết lại đề giúp mình
d) x - 3 phần 5 = -7 phần 10
\(\dfrac{x-3}{5}=\dfrac{-7}{10}=>5.-7=\left(x-3\right).10=>-35=\left(x-3\right).10=>x-3=-35:10=>x-3=\text{-3,5}=>x=\text{-3,5}+3=>x=6,5\)
`a)`
`13,2-x=-4,3`
`x=13,2-(-4,3)`
`x=17,5`
Vậy `x=17,5`
__________________________
`b)`
\(\dfrac{x}{3}=\dfrac{20}{15}\)
`=>x` `xx15=20xx3`
`x` `xx15=60`
`x=60:15`
`x=4`
Vậy `x=4`
__________________________
`c)`
\(\dfrac{2}{3}-\dfrac{1}{3x}=\dfrac{-5}{3}+\dfrac{1}{2}\\ \dfrac{2}{3}-\dfrac{1}{3x}=-\dfrac{7}{6}\\ \dfrac{1}{3x}=\dfrac{2}{3}-\left(-\dfrac{7}{6}\right)\\ \dfrac{1}{3x}=\dfrac{11}{6}\\ \Rightarrow1\times6=11\times3\times x\\ 6=33\times x\\ x=5,5\)
Vậy `x=5,5`
__________________________
`d)`
\(\dfrac{x-3}{5}=\dfrac{-7}{10}\)
`=>(x-3)xx10=5xx(-7)`
`(x-3)xx10=-35`
`x-3=-35:10`
`x-3=-3,5`
`x=-6,5`
Vậy `x=-6,5`
`@An`