Toán Lớp 7: |5/2X-3|-7/2=1/4, các bạn giúp mình với.

Question

Toán Lớp 7:  |5/2X-3|-7/2=1/4, các bạn giúp mình với.

diemchau · Answer

|$ frac{5}{2}$ x-3|-$ frac{7}{2}$ =$ frac{1}{4}$      =>|$ frac{5}{2}$ x-3|=$ frac{1}{4}$+$ frac{7}{2}$     =>|$ frac{5}{2}$ x-3|=$ frac{15}{4}$     => ( left[  begin{array}{l} frac{5}{2} x-3= frac{15}{4}   frac{5}{2} x-3=- frac{15}{4} end{array}  right. )      => ( left[  begin{array}{l} frac{5}{2} x= frac{15}{4}+3   frac{5}{2} x=- frac{15}{4}+3 end{array}  right. )      => ( left[  begin{array}{l} frac{5}{2} x= frac{27}{4}   frac{5}{2} x=- frac{3}{4} end{array}  right. )     => ( left[  begin{array}{l} x= frac{27}{4}: frac{5}{2}  x=- frac{3}{4}: frac{5}{2} end{array}  right. )     => ( left[  begin{array}{l} x= frac{27}{10}  x=- frac{-3}{10} end{array}  right. )     vậy ...

kimoanh34 · Answer

~ Bạn tham khảo ~    |5/2x-3|-7/2=1/4   =>|5/2x-3|=1/4+7/2   =>|5/2x-3|=15/4    (&rArr; left[  begin{array}{l} dfrac52x-3= dfrac{15}4   dfrac52x-3=- dfrac{15}4 end{array}  right. )    (&rArr; left[  begin{array}{l} dfrac52x= dfrac{27}4   dfrac52x=- dfrac{3}4 end{array}  right. )    (&rArr; left[  begin{array}{l}x= dfrac{27}{10}  x=- dfrac{3}{10} end{array}  right. )   Vậy x={27/10;-3/10}