Tìm x:
-13-x+8=-13
Tìm số nguyên x, biết 13 ⋮ (2x + 3)
A. x ∈ {1; -1; 13; -13} B. x ∈ {1; 13}
C. x ∈ {-1; 5; -2; -8} D. x ∈ {1; 2; 5; 8}
Tìm x ∈ Z thỏa mãn; -1 < x < 2
A. x ∈ {0} B. x ∈ {-1;0;1;2} C. x ∈ {0;1} D. x ∈ {0;1;2}
Sắp xếp các số 0;-12; -4; 9; 234; -234 theo thứ tự giảm dần, chọn câu đúng?
A. 234; 0; 9; -4; -12; -234 B. -234; -4; 0; -12; 9; 234
C. -234; -12; -4; 0; 9; 234 D. 234; 9; 0; -4; -12; -234
Tìm y biết: ( 7 x 13 + 8 x 13 ) : 9 2 3 - y = 39
Tìm y biết:
b) (7 x 13 + 8 x 13) : ( 2 3 – y) = 39
bài 1 : tìm x
a ) 2/3 . X = 2/7
b ) X : 8/13 = 13/7
c ) 3/2 : X = 7/4
a)\(x=\dfrac{2}{7}:\dfrac{2}{3}=\dfrac{3}{7}\)
b)\(x=\dfrac{13}{7}\times\dfrac{8}{13}=\dfrac{8}{7}\)
c)\(x=\dfrac{3}{2}:\dfrac{7}{4}=\dfrac{6}{7}\)
tìm x:
(x+13)⋮(x+8)
tìm x
213+(x-25)=-187
2.(x-2)+17=-13
x-8 -13=-8
x+11 +14=15
213 + (X - 25) = -187
=> x - 25 = -187 - 213
=> x = -187 - 213 + 25
=> x = -375
2.(x - 2) + 17 = -13
=> 2.(x - 2) = -13 - 17
=> 2.(X - 2) = -30
=> x - 2 = -30:2
=> x - 2 = -15
=> x = -15 + 2
=> x = -13
x - 8 - 13 = -8
=> x - 21 = -8
=> x = -8 + 21
=> x = 13
x + 11 + 14 = 15
=> x + 25 = 15
=> x = 15 - 25
=> x = -10
a) x- 25= -187 - 213 = -400
x= -400:25 = -16
b) 2.(x-2) = -13- 17 = -30
x- 2 = -30 :2 = -15
x= -15+2 = -13
c) x-8 = -8+13 = 5
x= 5+8 = 13
d) x+11 = 15-14 = 1
x= 1-11 = -10
Tính nhanh:
a)11/7 x 8/13 + 8/13 x 3/7 + 8/13
b)5/7 x 8/13 + 8/13 x 9/7 - 8/13
c)156 x 199 - 57 x 199 - 199
a.11/7.8/13+8/13.3/7+8/13
=8/13.(11/7+3/7+1)
=8/13.3
=24/13
b.5/7.8/13+8/13.9/7-8/13
=8/13.(5/7+9/7-1)
=8/13.1
=8/13
c.157.199-56.199-199
=199.(157-56-1)
=199.100
19900
a) Tìm y
( 13 x 7 + 13 x 8 ) : ( 29/3 - y ) = 39
tìm x biết : (x + 13) ⋮ (x+ 8)