\(x-25\%x=\dfrac{1}{2}\\x-\dfrac{25}{100}x=\dfrac{1}{2}\\ x-\dfrac{1}{4}x=\dfrac{1}{2}\\ x\left(1-\dfrac{1}{4}\right)=\dfrac{1}{2}\\ x\left(\dfrac{4}{4}-\dfrac{1}{4}\right)=\dfrac{1}{2}\\ x\cdot\dfrac{3}{4}=\dfrac{1}{2}\\ x=\dfrac{1}{2}:\dfrac{3}{4}\\ x=\dfrac{1\cdot4}{2\cdot3}\\ x=\dfrac{2}{3}\)
tìm số nguyên x
1) x+(x+1)+(x+2)+(x+3)+...+13+14=14
2) 25+24+23+...+x+(x-1)+(x-2)=25
1/ (\(\left(-\dfrac{2}{3}\right)\)\(^2\) x \(\dfrac{-9}{8}\) - 25% x \(\dfrac{-16}{5}\)
2/ -1\(\dfrac{2}{5}\) x 75% + \(\dfrac{-7}{5}\) x 25%
3/ -2\(\dfrac{3}{7}\) x (-125%) + \(\dfrac{-17}{7}\) x 25%
4/ (-2)\(^3\) x (\(\dfrac{3}{4}\) x 0.25) : (2\(\dfrac{1}{4}\) - 1\(\dfrac{1}{6}\))
Bài 1: Tính:
a) -25 . 63 - 25 . 3
Bài 2: Tìm x, biết:
c) ( x + 1 )2 = 16 d) ( -38 ) - ( x - 2 ) = -16
25 . 15 + 75 . 45
-10 . 25 - 10 . 75 + 10 . 50
3^x-2 - 2^3 = 19
(2 x - 5)^3 = - 64
2(x-1)^2 + 3 = 35
125 - 25 (x + 3) = 50
2(x+ 3) - 1x = 4
x + (x+1) + (x+2) + (x+3) + .... + 13 + 14 = 14
25 + 24 + 23 +...+ x + (x - 2) + (x – 3) = 25
Bài 1:Tìm số nguyên x biết: a,25-(-2+x+25)=-(10-379)+(-379-5)
b,(32-x)+(-7+/x/)-(/-x/+25)=-45
c,1+{-2-[-3+(-4+/x/)]}=1-[2-(-3-4)]
Quy tắc chuyển vế nha mọi người
a) (-1,25).17/21.(-0,4).7/34
b)0,5\(^{^{x+1}}\) + 0,5\(^x\) = 1,5
c) x:20-25%x=-1\(\dfrac{1}{5}\)
d) (x-1)\(^2\) =1
e) 5\(^3\) : 25+2\(^4\) :4
Tìm x,biết:
x+(x+1)+(x+2)+(x+3)+.........+24+25=25
1, \(\left(\dfrac{1}{3}-x\right)^2=\dfrac{9}{25}\)
2, \(\left(5-x\right)^2=25\)
1 TIM X
a,(x^2+5) nhan (x^2-25)=0
b,(x^2-5)nhan (x^2-25)<0
