Question

Sa se rezolve in R urmatoarele ecuatii :
a) x+10=5
b)2x+7=-9
c) 1 pe 3 x + 1 pe 3=x-1
d)2(x+3)-3(x+1)=9

Answer 1

x+10=5
x=5-10
x=-5

2x+7=-9
2x=-9-7
2x=-16
x=-8

2x+6-3x-3=9
-x+3=9
-x=9-3
-x=6

1/3x+1/3=x-1
1/3x-x=-1-1/3

Answer 2

a) x+10=5
x=5-10
x= - 5

b)2x+7=-9
2x=9-7
x=2/2
x=1

c) 1 pe 3 x + 1 pe 3=x-1
1/3x+1/3=x-1
1+x=3x(x-1)
1+x=3x²-3x
3x²-3x-x-1
3x²-4x-1
Δ=14-12=4
x1=(4+√4)/6
x1=6/6
x1=1
x2=(4-2)/6
x2=1/3

d)2(x+3)-3(x+1)=9
2x+6-3x-3=9
3-9=x
x=-6