Question

cứu tôi

(x+30).4=(x-30).5

Answer 1

\(\left(x+30\right)4=\left(x-30\right).5\)

\(4x+120=5x-150\)

\(120+150==5x-4x\)

\(270=x\)

Answer 2

(x + 30).4 = (x - 30).5 

4x + 120 = 5x - 150 

150 + 120 = 5x - 4x 

=> x = 270 

Answer 3

4x+120=5x-150

120+150=5x-4x

x=270

Answer 4

\(x\in\infty,-\infty\)

\(\left(x+30\right)4=4\left(x+30\right)\)

\(\left(x-30\right)5=5\left(x-30\right)\)

\(4\left(x+30\right)=5\left(x-30\right)\)

\(4x+120=5x-150\)

\(-x=-270\)

\(\Rightarrow x=270\)

Answer 5

( x + 30 ) . 4 = ( x - 30 ) . 5

=> 4x + 120 = 5x . 150

=> 4x - 5x    = -120 - 150

=> -x           = -270

=>  x           = 270

Vậy x = 270

k nha !!!