\(\frac{x-20}{x-10}=\frac{x+40}{x+70}\)
\(\Rightarrow\left(x-20\right)\left(x+70\right)=\left(x-10\right)\left(x+40\right)\)
\(\Rightarrow x^2+70x-20x-1400=x^2+40x-10x-400\)
\(\Rightarrow x^2+70x-20x-x^2-40x+10x=1400-400\)
\(\Rightarrow20x=1000\Rightarrow x=50\)
Tìm x, biết: (x-20):(x-10)=(x+40):(x+70)
Tìm x biết:
(x - 20) : ( x + 40)= ( x -10) : ( x +70)
Tìm x, biết:
a) (x+15) : x = 4:3
b) (x-20) : (x-10) = (x+40) : (x+70)
Tìm x biết \(\frac{x-20}{x-10}=\frac{x+40}{x+70}\)
Tìm x, biết :
a) (x + 15) : x = 4:3
b) (7,5 - x) : (3,5 + x) = 5:6
c) (x - 20) : (x - 10) = (x + 40) : (x + 70)
Tìm x biết:
a, (x+15):x =4:3
b, (7,5-x) :(3,5+x)= 5:6
c, (x+20):(x-10)=(x+40):(x+70)
Tìm x :
x-20 x+40
____ = _____
x-10 x+70
\(\frac{x-20}{x-10}=\frac{x+40}{x+70}\)
bài 1
a,(x+7) :x=4:5
b,(x-20):(x+40)=(x+70):(x-10)
