Question

Determinati numarul natural x astfel incat fractia:
a) x supra 5
b) 15 supra 5x
c) x+2 supra 10
d) 2x+3 supra 15
e) 3x supra 15
f) 3+5x supra 7+x
g) 2(x+1)-1 supra 4x-7
Sa fie echiunitara

Answer 1

Echiunitara asta inseamna numitorul = numaratorul
a) x=5
b) x×5=15 => x=3
c) x+2=10 => x=8
d) 2x+3=15 => 2x=12 x=6
e) 3x=15 |=> x=5
f) 3+5x=7+x => 4x=4 => x=1
g) 2x+2-1=4x-7 => 8=2x => x=4

Answer 2

a) x=5; b) 15=5x, x=3; c) x+2=10, x= 8; d) 2x+3=15, 2x=12, x=6; e) 3x=15, x=5; f) 3+5x=7+x, 4x=4, x=1; g) 2x+2-1 =4x-7, 2x=7+1=8, x=4
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