-12(x-15)+7(3-x)=15
tìm các số nguyên x , biết
a, ( x+7) . (x-15)
b, 8x + (-7) . x = -33
c, -12 . ( x - 5) + 7 . (3 - x) = 5
d,(-2) . (x +1) - (x - 5) = -2x
e, (-2) . x + 5 = (-3) . (-3) + 8
g, -12x = 15.(-4) - 12
b: =>x(8-7)=-33
=>x=-33
c: =>-12x+60+21-7x=5
=>-19x=-76
hay x=4
d: =>-2x-2-x+5+2x=0
=>3-x=0
hay x=3
x-(-7)=-8+(-2)
x+(12-15)=/-3/-7
(12-x )-(-10)=-25
(-20)-(15-x )=-50
a) x - (-7) = -8 + (-2)
x + 7 = -8 - 2
x + 7 = -10
x = -10 - 7
x = -17
b) x + (12 - 15) = /-3/ - 7
x + (-3) = 3 - 7
x - 3 = -4
x = -4 + 3
x = -1
c) (12 - x) - (-10) = -25
(12 - x) + 10 = -25
12 - x = -25 - 10
12 - x = -35
x = 12 - (-35)
x = 12 + 35 = 47
d) (-20) - (15 - x) = -50
15 - x = -20 - (-50)
15 - x = -20 + 50
15 - x = -30
x = 15 - (-30)
x = 15 + 30
x = 45
Tìm x :
-12 (x - 15) + 7 (3 - x) = 15
Tìm x :
-12 (x - 15) + 7 (3 - x) = 15
Tìm x :
-12 (x - 15) + 7 (3 - x) = 15
Tìm x :
-12 (x - 15) + 7 (3 - x) = 15
a) 42-x=5
b) 15.(x+4)=75
c) 27+3x=9^8.9^7
d) x+18=12
e) 2x-15=-19
f) 36 :(x^3-12)=-3
g)x+15=35
h) 2x-13=3^2
a) 42 - x = 5
x = 42 - 5
x = 37
b) 15.(x + 4) = 75
x + 4 = 75 : 15
x + 4 = 5
x = 5 - 4
x = 1
d) x + 18 = 12
x = 12 - 18
x = -6
e) 2x - 15 = -19
2x = (-19) + 15
2x = -4
x = -4 : 2
x = -2
f) 36 : (x^3 - 12) = -3
x^3 - 12 = 36 : (-3)
x^3 - 12 = -12
x^3 = 0
=> x = 0
g)x + 15 = 35
x = 35 - 15
x = 20
h) 2x - 13 = 3^2
2x - 13 = 9
2x = 9 + 13
2x = 22
x = 22 : 2
x = 11
a) 42-x=5
x=42-5
x= 37
b)15*(x+4)=75
x+4=75:15
x+4=5
x =5-4
x = 1
a) 42 - x = 5
x = 42 - 5
x = 37
b) 15.(x + 4) = 75
x + 4 = 75 : 15
x + 4 = 5
x = 5 - 4
x = 1
d) x + 18 = 12
x = 12 - 18
x = -6
e) 2x - 15 = -19
2x = (-19) + 15
2x = -4
x = -4 : 2
x = -2
f) 36 : (x^3 - 12) = -3
x^3 - 12 = 36 : (-3)
x^3 - 12 = -12
x^3 = 0
=> x = 0
g)x + 15 = 35
x = 35 - 15
x = 20
h) 2x - 13 = 3^2
2x - 13 = 9
2x = 9 + 13
2x = 22
x = 22 : 2
x = 11
a, x-(-7)=-8+(-2) b, x+(12-15)=/-3/-7
c, (12-x )-(-10)=-25
d, (-20)-(15-x )=-50
Tính bằng cách thuận tiện
a) 5 x 11 x 15 x 18/6 x 15 x 22 x 10
b) 7/12 x 3/5 + 3/5 x 5/12
a, \(\dfrac{5\times11\times15\times18}{6\times15\times22\times10}\)
= \(\dfrac{5\times11\times15\times6\times3}{6\times15\times11\times2\times2\times5}\)
= \(\dfrac{5\times11\times15\times6}{5\times11\times15\times6}\) \(\times\) \(\dfrac{3}{2\times2}\)
= 1 \(\times\) \(\dfrac{3}{4}\)
= \(\dfrac{3}{4}\)
b, \(\dfrac{7}{12}\) \(\times\) \(\dfrac{3}{5}\) + \(\dfrac{3}{5}\) \(\times\) \(\dfrac{5}{12}\)
= \(\dfrac{3}{5}\) \(\times\) ( \(\dfrac{7}{12}+\dfrac{5}{12}\))
= \(\dfrac{3}{5}\) \(\times\) \(\dfrac{12}{12}\)
= \(\dfrac{3}{5}\) \(\times\) 1
= \(\dfrac{3}{5}\)