Question

x=?
a) 2+2*[1+2*(1+2x)]=80
b) (x+1)(x+2)=56
c) (x/50+30)/6-6=0
d) [2*(x+2)*5+3*(x+2)]*7=273

Answer 1

a)
4*[1+2(1+2x)]=80
4(1+2+4x)=80
4+8+16x=80
16x=80-4-8
16x=68
x=68/17 sau 17/4
b)
x^2+2x+x+2=56
x^2+3x+(2-56)=0
x^2+3x-54=0
delta=b^2-4ac , unde a=1 b=3 c=-54
delta=9-(-4*-54) ,delta<0 , ecuatia nu are solutii
c)
impartirea la 0 nu are sens
d)
[2*(x+2)*5+3*(x+2)]*7=273
[(2*5)(x+2)+3x+6] *7=273
7*[(10*(x+2)+3x+6]=273
7*(10x+20+3x+6)=273
7*(13x+26)=273
91x+182=273
91x=273-182
91x=91
x=91/91 adica =1