Question

[PhuongLinh LeHoang]

( x-17)/33 + (x-21)/29 + x/25 =4

(3x-5)(7-5x)+(5x+2)(3x-2) =2

Answer 1

[PhuongLinh LeHoang]

a) (x-17)/33 + (x-21)/29 + x/25 = 4 <=> [(x-17)/33-1] + [(x-21)/29-1] + x/25-2] = 0 <=> (x-50)/33 + (x-50)/29 + (x-50)/25 = 0 <=> (x-50)(1/33+1/29+1/25) = 0 Mà 1/33+1/29+1/25 khác 0. <=> x- 50 = 0 <=> x=50 b) (3x−5)(7−5x)+(5x+2)(3x−2)=2 <=> 21x−15x2−35+25x+15x2−10x+6x−4−2=0 <=> (15x2−15x2)+(25x+21x−10x+6x)−(35+4+2)=0 <=> 42x=41 <=> x=41/42