a) \(\frac{5}{12}=\frac{x}{72}\)
\(\Rightarrow5\cdot72=12\cdot x\)
\(\Rightarrow360=12\cdot x\)
\(\Rightarrow x=\frac{360}{12}=30\)
b) \(\frac{x+3}{15}=\frac{-1}{3}\)
\(\Rightarrow\left(x+3\right)\cdot3=15\cdot\left(-1\right)\)
\(\Rightarrow\left(x+3\right)\cdot3=-15\)
\(\Rightarrow x+3=-15:3=-5\)
\(\Rightarrow x=-5-3=-8\)
a) 5/12 = x /72
Vì 5. 72 = 12 .x
=> x = 5 .72 : 12
=> x = 30
b) x + 3/ 15 = -1/3
Vì ( x+3). 3 = 15. (-1)
=> x +3 = 15.( -1) : 3
=> x +3 = - 5
=> x = -5 - 3
=> x = -8
A= \(\frac{5}{12}=\frac{x}{72}\)
=> x= \(\frac{72.5}{12}\)
=> x= 30
Hai da mạng lag nên phần b tự làm ạ!
__Yu__
thank you mọi người