Bài 1:
a) \(\left| x \right| = {2 \over 3}\)
\(\Rightarrow x = {2 \over 3}\) hoặc \(x = {{ - 2} \over 3}\).
b) \({3 \over 2} - \left| x \right| = {1 \over 4} \)
\(\Rightarrow \left| x \right| = {3 \over 2} - {1 \over 4} \)
\(\Rightarrow \left| x \right| = {{6 - 1} \over 4}\)
\(\Rightarrow \left| x \right| = {5 \over 4}\)
\( \Rightarrow x = {5 \over 4}\) hoặc \(x = - {5 \over 4}.\)
c) \(\left| {{5 \over {18}} - x} \right| - {7 \over {24}} = 0 \)
\(\Rightarrow \left| {{5 \over {18}} - x} \right| = {7 \over {24}}\)
\( \Rightarrow {5 \over {18}} - x = {7 \over {24}}\) hoặc \({5 \over {18}} - x = - {7 \over {24}}\)
\( \Rightarrow x = {5 \over {18}} - {7 \over {24}}\) hoặc \(x = {5 \over {18}} + {7 \over {24}}\)
\( \Rightarrow x = - {1 \over {72}}\) hoặc \(x = {{41} \over {72}}.\)
Bài 2:
a) \( - 0,320 + \left( { - 1,151} \right) = - 1,471\)
b) \( - 4,15 - 0,273 = - 4,423.\)
