Vì lười nên không thèm suy nghĩ mà lm lun
a) y+ 30%y = -1,3 b) y- 25% y = 1/2 c) \(3\frac{1}{3}y+16\frac{3}{4}=-13,25\)
y+3/10y = -1,3 y- 1/4y =1/2 \(\frac{10}{3}y+16,75=-13,25\)
13/10 y = -1,3 3/4 y =1/2 \(\frac{10}{3}y=-20\)
y = -1 y = 2/3 \(y=-6\)
:w
a) \(y+30\%.y=-1,3\)
\(y.10+\frac{3}{10}.y.10=-1,3\)
10.y + 3.y = -13.10
13.y = -13
y = -13 : 13
y = -1
=> y = -1
b) \(y-25\%.y=\frac{1}{2}\)
\(y-\frac{1}{4}.y=\frac{1}{2}\)
\(y.4-\frac{1}{4}.y=\frac{1}{2}.4\)
4y - y = 2
3y = 2
y = 2 : 3
\(y=\frac{2}{3}\)
\(\Rightarrow y=\frac{2}{3}\)
c) \(3\frac{1}{3}y+16\frac{3}{4}=-13,25\)
\(\frac{10}{3}.y+\frac{67}{4}=-13,25\)
\(\frac{10}{3}.y=-13,25-\frac{67}{4}\)
\(\frac{10}{3}.y=-30\)
\(y=-30:\left(\frac{10}{3}\right)\)
y = -9
=> y = -9
K hiểu phần nào ib tớ giải thích
\(\text{a) }y+30\%y=-1,3\)
\(\Rightarrow y+\frac{3}{10}y=-\frac{13}{10}\)
\(\Rightarrow y\left(1+\frac{3}{10}\right)=-\frac{13}{10}\)
\(\Rightarrow y.\frac{13}{10}=-\frac{13}{10}\)
\(\Rightarrow y=-1\)
\(\text{b) }y-25\%y=\frac{1}{2}\)
\(\Rightarrow y-\frac{1}{4}y=\frac{1}{2}\)
\(\Rightarrow y\left(1-\frac{1}{4}\right)=\frac{1}{2}\)
\(\Rightarrow y.\frac{3}{4}=\frac{1}{2}\)
\(\Rightarrow y=\frac{2}{3}\)
\(\text{c) }3\frac{1}{3}y+16\frac{3}{4}=-13,25\)
\(\Rightarrow\frac{10}{3}y+\frac{67}{4}=-\frac{1325}{1000}\)
\(\Rightarrow\frac{10}{3}y=-\frac{1325}{1000}-\frac{67}{4}\)
\(\Rightarrow\frac{10}{3}y=-\frac{53}{40}-\frac{67}{4}\)
\(\Rightarrow\frac{10}{3}y=\frac{-723}{40}\)
\(\Rightarrow y=-5,4225\)
a)y+30%y =-1,3
y.(30%+1) =-13/10
y.(30/100+1) =-13/10
y.(3/10+1) =-13/10
y.(3/10+10/10) =-13/10
y.13/10 =-13/10
y =-13/10:13/10
y =-1
b)y-25%y =1/2
y.(1-25%) =1/2
y.(1-25/100) =1/2
y.(1-1/4) =1/2
y.3/4 =1/2
y =1/2:3/4
y =1/2.4/3
y =2/3
tớ chỉ giúp cậu được 2 câu đầu thôi