Bonjour,
1)
3/10 *(5/6 - 10/8)
= 3/10 * (40/48 - 60/48)
= 3/10 * (-20/48)
= 3/10 * (- 5/12)
= -15/ 120
= -3/24
2)
-3/16 * -5/2 = 15 /32
= (15/32 )/( -9/32)
= 15/32 * (-32/9)
= -15/9
= - 5/3
3)
20/24 - 42/24 + 3/24
= -19/24
AB =?
Pythagore
AB² = AH² + BH²
= 3²+ 2²
AB²= 9 + 4 = 13
AC² = AH² + HC²
= 3² + 4,5²
AC² = 9+20,25 =29,25
BC² = AB² + AC²
BC = 2+4,5 = 6,5
6,5² = 13 + 29,25
42,25 = 42,25
Le triangle est rectangle.
