Question

[Phạm Quang ??]

Giúp mình vs mn ơi. Mai mình cần rồi :

Giải các PT:
a) 3(x-4)+5=2(x+1)-8

b) 5(x+1)²+2x=5x²-3

c) \(\frac{4\left(x+2\right)}{15}=\frac{13x-9}{40}\)

d)\(\left(\frac{3}{4}x-1\right)\left(\frac{5}{3}x+2\right)=0\)

e)\(\frac{3x-1}{x-1}-\frac{2x+5}{x+3}-\frac{8}{x^2+2x-3}=1\)

Cảm ơn mn trước nhé!

Answer 1

[Le Tran Bach Kha]

a) \(3\left(x-4\right)+5=2\left(x+1\right)-8\)

\(\Leftrightarrow3x-12+5=2x+2-8\)

\(\Leftrightarrow x=1\)

Vậy : \(S=\left\{1\right\}\)

b) \(5\left(x+1\right)^2+2x=5x^2-3\)

\(\Leftrightarrow5x^2+10x+5+2x=5x^2-3\)

\(\Leftrightarrow12x=-8\)

\(\Leftrightarrow x=-\frac{2}{3}\)

Vậy : \(S=\left\{-\frac{2}{3}\right\}\)

c) \(\frac{4\left(x+2\right)}{15}=\frac{13x-9}{40}\)

\(\Leftrightarrow32\left(x+2\right)=3\left(13x-9\right)\)

\(\Leftrightarrow32x-39x=-27-64\)

\(\Leftrightarrow-7x=-91\)

\(\Leftrightarrow x=13\)

Vậy : \(S=\left\{13\right\}\)