Question

2/Tìm x, biết:

a)   x + 0,5 = 3/2

b)   3 4/5 - x = 4/5

c)    3_* x + 2 _* x = 20

d)    2 : x = 3/4

Answer 1

\(a\)) \(x+0,5=\frac{3}{4}\)

\(x+\frac{5}{10}=\frac{3}{4}\)

\(x=\frac{3}{4}-\frac{5}{10}\)

\(x=\frac{1}{4}\)

b) \(3\frac{4}{5}-x=\frac{4}{5}\)

\(\frac{19}{5}-x=\frac{4}{5}\)

\(x=\frac{19}{5}-\frac{4}{5}\)

\(x=\frac{15}{5}=3\)

c) \(3\times x+2\times x=20\)

\(\left(3+2\right)\times x=20\)

\(5\times x=20\)

\(x=20\div5\)

\(x=4\)

d) \(2\div x=\frac{3}{4}\)

\(x=2\div\frac{3}{4}\)\(x=\frac{8}{3}\)