Tìm X
a/ X : 3 = 12 642
b/ X + 21 415 = 56 743
Tìm x ∈ ℤ ,biết:
a ) 27 23 + − 4 23 + 1 2 + − 4 8 < x < 7 3 + 13 41 + 28 41 b ) 4 5 + − 17 25 + − 2 5 + 17 25 < x ≤ 7 43 + 5 6 + 7 − 43 + 3.
a) 1 < x < 10 3 = > x ∈ {2;3}
b) 2 5 < x ≤ 23 6 = > x ∈ {1;2;3}
Tìm x, biết:
a ) 2 | x | − 1 2 = 3 4 b ) 2 x − 1 3 + 5 6 = 1 c ) 1 2 − 3 x + 4 1 5 = 6 2 5 d ) 17 2 − 2 x − 3 4 = − 7 4
Chú ý rằng |a| = b với b > 0 thì a = b hoặc a = - b.
a ) x ∈ − 5 8 ; 5 8 b ) x ∈ 1 12 ; 1 4
c ) x ∈ − 17 30 ; 9 10 d ) x ∈ − 19 4 ; 11 2
tìm x
a, |x+3| -12 = |-5|
b, 25 - (x-5) = 415 x (15 - 415 )
a, | x + 3 | - 12 = | -5 |
x + 3 - 12 = 5
x + 3 = 5 + 12
x + 3 = 17
x = 17 - 3 = 14
b, 25 - ( x- 5 ) = 415 x ( 15 - 415 )
25 - ( x - 5 ) = 415 x ( - 400 )
25 - ( x - 5 ) = - 166000
x - 5 = 25 - ( - 166000)
x - 5 = 166025
x = 166025 + 5
x = 166030
CHÚC BẠN HỌC TỐT
bài 1: tìm x, biết
a, 3-(17-x)=289-(36+289)
b,25-(x+5)=(-415)-(15-415)
c,34+(21-x)=(3747-30) -3746
a)-22: b)35: c)84
Tìm x :
a) 3x-17=x+3
b) |x-3|-12=|-5|
c) 2,5-(x-5)=-415-(15-415)
a) 3x-17=x+3
3x-x=17+3
2x=20 =>x=10
b) |x-3|-12=|-5|
|x-3|=17
x-3=17 hoặc x-3=-17
nếu x-3=17 thì x=20
nếu x-3=-17 thì x=-14
c) 2,5-(x-5)=-415-(15-415)
2,5-(x-5)=-15
x-5=2,5+15
x-5=17,5 =>x=22,5
a,3x-17=x+3
3x-x=3+17
2x=20
x=20:2
x=10
b,/x-3/-12=/-5/
/x-3/-12=5
/x-3/=17
suy ra ; x-3=-17 or x-3=17
x=-17+3 x =17+3
x=-14 x=20
c,2,5-(x-5)=-415-(15-415)
2,5-(x-5)=-15
x-5=2,5-(-15)
x-5=17,5
x=17,5+5
x=22,5
x=-14
tìm số nguyên x,biết
a/ 3-(17-x)=289-(36+289)
b/ 25-(x+5)=-415-(15-415)
c/ 34+(21-x)=(3747-30)-3746
Câu 1
3216x58
492x207
60228:42
95046:124
Câu 2 tìm x
Xx135+642=8202
2835:x+415=450
Câu 1:
3216 x 58 = 186 528
492 x 207 = 101 844
60 228 : 42 = 1 434
95 046 : 124 = 766.5
Câu 2 :
X . 135 + 642 = 8202
X . 135 = 8202 - 642
X . 135 = 7560
2835 : X + 415 = 450
2835 : X = 450 - 415
2835 : X = 35
X = 2835 : 35
X = 81
=1865
=101844
=1434
=766.5
x135=8202-642=7560
x=7560:135=56
2835:x=450-415=35
x=2835:35=81
câu 1 : 186528
101844
1434
766,5
câu 2 : x * 135 + 642 = 8202
x = (8202 - 642) : 135
x= 56
2835 : x +415 = 450
x = 2835 :( 450 - 415 )
x = 81
Tính Nhanh:
a) 5/12*4/9+4/9*7/12 b) (13/21*7/8-12/21*7/8)*12 c) 7/11+3/4+4/11+8/17+1/4+18/34
Tìm x:
a) 3,71+(632-x)=415
b) 140:(5*x-15)=4
c) 84:(324:18+36-x)+15=19
a \(\dfrac{5}{12}\times\dfrac{4}{9}\) + \(\dfrac{4}{9}\times\dfrac{7}{12}\)
= \(\dfrac{4}{9}\times\left(\dfrac{5}{12}+\dfrac{7}{12}\right)\)
= \(\dfrac{4}{9}\times\dfrac{12}{12}\)
= \(\dfrac{4}{9}\)
b(\(\dfrac{13}{21}\times\dfrac{7}{8}-\dfrac{12}{21}\times\dfrac{7}{8}\)) x 12
(\(\dfrac{7}{8}\times\left(\dfrac{13}{21}-\dfrac{12}{21}\right)\))x 12
\(\dfrac{7}{8}\times\dfrac{1}{21}\) x 12
\(\dfrac{139}{14}\)
\(\dfrac{7}{11}+\dfrac{3}{4}+\dfrac{4}{11}+\dfrac{8}{17}+\dfrac{1}{4}+\dfrac{18}{34}\)
=\(\left(\dfrac{7}{11}+\dfrac{4}{11}\right)+\left(\dfrac{3}{4}+\dfrac{1}{4}\right)\) + \(\dfrac{18}{34}\)
=1 + 1 + \(\dfrac{18}{34}\)
=\(\dfrac{34}{17}\)
2)a 3,71 + (632 - x) = 415
632 - x= 415 - 3,71
632 -x = 411,59
x = 632 - 411,59
x = 220,41
b, 140 : (5x \(x\) - 15) = 4
5x \(x\) - 15 = 140 : 4
5x \(x\) - 15 = 35
5x \(x\) = 35 + 15
5x \(x\) = 50
\(x\) = 50 : 5
\(x\) = 10
tìm tất cả các số nguyên x thỏa mãn
3 - (17-x)=289-(36+289)
25-(x+5)=-415-(15-415)
34+(21-x)=(3747-30)-3746