winner123

Verified answer

Bonjour

1) MC = 5 - x

2 a) MA² = 2 ² + x²

2 b) MD² = 2² + ( 5 - x)²

2 c) Ma² + MD² = 2² + x² + 2 ² + ( 5 - x)²
   = 4 + x² + 4 + 25 - 10 x + x² = 2 x² - 10 x + 33

3 a) 2 x² - 10 x + 33 = 5²
       2 x² - 10 x + 33 = 25
       2 x² - 10 x  + 33 - 25 = 0
       2 x² - 10 x + 8 = 0

3 b ) (x -1) (2 x -8) = 2 x² - 8 x - 2 x + 8 = 2 x² - 10 x + 8

3 c)  ( x-1) ( 2 x -8) = 0
         soit x - 1 = 0 et x  = 1
soit 2 x - 8 = 0
2 x = 8 et x = 4