Răspuns:
a,c,e,g admit x=2
Explicație pas cu pas:
deoarece a)2²=4=>2×2=4=>4=4(adevărat)
b)3×2²=6=>3×4=6=>12=6(fals)
c)(-2)²=4=>(-2)×(-2)=4=>4=4(- inmultit cu - face mereu +)(adevarat)
d)2²=-4=>2×2=-4=>4=-4(fals)
e)2×2²=8=>2×4=8=>8=8(adevarat)
f)2²-1=15=>4-1=15=>3=15(fals)
g)2²+5=9=>4+5=9=>9=9(adevarat)
h)3×2²-6=-6=>3×4-6=-6=>12-6=-6=>6=-6(fals)
