Question

a) (x+1)+(x+2)+(x+3)+(x+4)=1+2+3+4
b) 5x-3=4x
c) -2x+1=2x-1
d) 4(x+1)=4x
e) 3(x-1)=3x-3

Answer 1

$\displaystyle a).(x+1)+(x+2)+(x+3)+(x+4)=1+2+3+4 \\ x+1+x+2+x+3+x+4=1+2+3+4 \\ x+x+x+x=1+2+3+4-1-2-3-4 \\ 4x=0 \\ x=0 \\ b).5x-3=4x \\ 5x-4x=3 \\ x=3 \\ c).-2x+1=2x-1 \\ -2x-2x=-1-1 \\ -4x=-2 \\ x= \frac{2}{4} \Rightarrow x= \frac{1}{2}$
$d). 4(x+1)=4x \\ 4x+4=4x~Fals$
$e).3(x-1)=3x-3 \\ 3x-3=3x-3 ~Adevarat$