Toán Lớp 8: Tìm x:
a. x^2-25 –( x+5 ) = 0
b. 3x (x-2) – x+ 2 = 0
c. x( x – 4) – 2x + 8 = 0
d. 3x (x + 5) – 3x – 15=0
e. ( 3x – 1)^2 –( x +5)^2=0
f. ( 2x -1)^2 – ( x -3)^2=0
g.(2x -1)^2- (4×2 – 1) = 0
g. x^2 (x^2 + 4) – x^2 – 4 = 0
i.x^4 – x^3 +x^2 – x =0
k. 4x^2 – 25 –( 2x -5)(2x +7)=0
l.x^3 – 8 – (x -2)(x -12) = 0
m. 2(x +3) –x^2– 3x=0