Question

Rezolva ecuatiile: 7(x+1/5)=1intreg3/4; 14/9(x-1)=7/4; 6/5(x-0,5)=12; 7(x-1/2)=15/14;
1/8+1/2 ori (2x-1)=2x-1/8 ori (8x-1)-1/4 ori (4x-2); x-1 totul supra 2 +x+2 totul supra 4 +1/3=x+6 totul supra 6 +1intrg 7/12;
x+1 totul supra 2 + 2x+6 totul supra 3 =3x+21 totul supra5

Answer 1

7(x+1/5)=7/4 |:7
x+1/5=1/4 |·20
20x+4=5
20x=1
x=1/20
S={1/20}

14/9 ·(x-1)=7/4 |:7
2/9(x-1)=1/4
x-1=1/4:2/9
x-1=1/4·9/2
x-1=9/8
x=9/8+8/8
x=17/8=2 1/8=2,125
S={2,125}

6/5(x-0,5)=12
x-0,5=12:6/5
x-0,5=12·5/6
x-0,5=10
x=10,5
S={10,5}

7(x-1/2)=15/14 |:7
x-1/2=15/98
x=15/98+49/98
x=64/98=32/49
S={32/49}

1/8+1/2·(2x-1)=2x-1/8·(8x-1)-1/4·(4x-2) |·8
1+4(2x-1)=16x-(8x-1)-2(4x-2)
1+8x-4=16x-8x+1-8x+4
8x-3=5
8x=8
x=1
S={1}

(x-1)/2+(x+2)/4+1/3=(x+6)/6+19/12 |·12
6(x-1)+3(x+2)+4=2(x+6)+19
6x-6+3x+6+4=2x+12+19
9x+4=2x+31
7x=27
x=27/7=3 6/7
S={27/7}

(x+1)/2+(2x+6)/3=(3x+21)/5 |·30
15(x+1)+10(2x+6)=6(3x+21)
15x+15+20x+60=18x+126
35x+75=18x+126
17x=51
x=3
S={3}