tìm x biết
(x+1)+(x+2)+......+(x+9)+(x+10)=25
tìm x biết
1) 9-25=(7-x)-(25+7)
2) (27-514) -(486-73)+x=7
3) 25+5+37-25+6-29-x=37
4) 14+(-12)+x =10-/-15/+ /-3/
1) 9-25=(7-x)-(25+7)
(7-x)-(25+7)=9-25
(7-x)-(25+7)=-16
(7-x)-32=-16
7-x=-16+32
7-x=16
x=7-16
x=-9
2) (27-514) -(486-73)+x=7
(27-514) -(486-73)+x=7
-487-413+x=7
-1011+x=7
x=7-(-1011)
x=7+1011
x=1018
3) 25+5+37-25+6-29-x=37
25+5+37-25+6-29-x=37
67-25+6-29-x=37
42+6-29-x=37
48-29-x=37
19-x=37
x=19-37
x=-18
4) 14+(-12)+x =10-/-15/+ /-3/
14+(-12)+x =10-15+3
14+(-12)+x =-5+3
14+(-12)+x =-2
2+x=-2
x=-2-2
x=-4
tìm x nguyên , biết
a, (1/16)^x = (1/12)^10
b, 8/25 = 2^x/5^x-1
c, 9^x:3^x=3
Tìm số nguyên x , biết rằng :
a) x+13=5
b)x-1=-9
c)25-/x/ =10
d) /x-2/ +7 = 12
a, => x = 5 - 13 = -8
b, => x = -9 + 1 = -8
c, => |x| = 25 - 10 = 15
=> x = 15 hoặc x = -15
d, => |x-2| = 12 - 7 = 5
=> x-2 =5 hoặc x-2 = -5
=> x=7 hoặc x=-3
Tìm x biết:
a, (x + 9)×9 = 81
b, (x + 24)÷9 = 7
c, x - 56 = 8×9
d, x + 25 = 9×10
tìm các số nguyên x biết:(x^2-4/25).(x^2-4).(x^2-16/9).(x^2-10)<0
tìm x thuộc z biết :
a) (-2).(7+x)<0
b)(x-1).(x+2)<0
c)(x^2-9).(2x+10)=0
d)(x-2)^2-25=0
a.-2 .(7 + x) < 0
ta có:- . + = - (khác 0)
- < 0
=>7 + x = -1;-2;-3;-4;...
x = -6;-5;-4;...
b.(x - 1) . (x + 2) < 0
ta có: - . + = - hoặc + . - = -
=>(x - 1) . ( x + 2) = -
=>x = -1
c.(x^2 - 9).(2x + 10) = 0
=> (x^2 - 9) = 0 hoặc (2x + 10) = 0
x^2 - 9 =0
x^2 =0 + 9
x^2 = 9
x = 3 hoặc -3
2x + 10=0
2x = 0 - 10
2x = -10
x = -10 : 2
x = -5
vậy: x thuộc {3;-3;5}
d.(x - 2)^2 - 25=0
(x - 2 )^2 = 0 + 25
(x - 2)^2 = 25
x - 2 =5
x = 5 + 2
x =7
Tìm x biết
a) (x-1/2)^2=4
b) 10/1/2-(x+1/3)^2=1/1/2
c) (x-1/5)^2+17/25=26/25
d) 1/5/27+(3x-7/9)^3=24/27
a) (x - 1/2)2 = 4
<=> (x - 1/2)2 = 22
<=> x - 1/2 = -2; 2
<=> x - 1/2 = 2 hoặc x - 1/2 = -2
x = 2 + 1/2 x = -2 + 1/2
x = 5/2 x = -3/2
=> x = 5/2 hoặc x = -3/2
b) 10/1/2 - (x + 1/3)2 = 1/1/2
<=> -(x + 1/3)2 = 1/1/2 - 10/1/2
<=> -(x + 1/3)2 = 1/2 - 5
<=> -(x + 1/3)2 = -5.2 + 1/2
<=> -(x + 1/3)2 = -9/2
<=> (x + 1/3)2 = 9/2
<=> x + 1/3 = \(\sqrt{\frac{9}{2}}\) hoặc x + 1/3 = \(-\sqrt{\frac{9}{2}}\)
x = \(\frac{3\sqrt{2}}{2}\) - 1/3 x = \(-\frac{3\sqrt{2}}{2}\) -1/3
=> x = \(\frac{3\sqrt{2}}{2}\) - 1/3 hoặc x = \(-\frac{3\sqrt{2}}{2}\) -1/3
c) (x - 1/5)2 + 17/25 = 26/25
<=> (x - 1/5)2 = 26/25 - 17/25
<=> (x - 1/5)2 = (3/5)2
<=> x - 1/5 = -3/5; 3/5
<=> x - 1/5 = 3/5 hoặc x - 1/5 = -3/5
x = 3/5 + 1/5 x = -3/5 + 1/5
x = 4/5 x = -2/5
=> x = 4/5 hoặc x = -2/5
tìm x
a.9/25-12/25:x=1/5
b.8/17*x+2/9=10/27
tìm x
a.9/25-12/25:x=1/5
12/25:x=9/25 - 1/5
12/25:x=4/25
x=12/25 : 4/25
x=1/3
b.8/17*x+2/9=10/27
8/17*x=10/27 - 2/9
8/17*x=4/27
x=4/27 : 8/17
x=17/45
tìm x
a.9/25-12/25:x=1/5
b.8/17*x+2/9=10/27
a: =>12/25:x=9/25-1/5=4/25
=>x=3
b: =>8/17x=10/27-2/9=10/27-6/27=4/27
hay x=17/54