Réponse:
DE =6
AC=14,4
BC=18
Explications étape par étape:
[tex] {be }^{2} = {bd}^{2} + {de}^{2} \\ {de}^{2} = {be}^{2} - {bd}^{2} \\ {de}^{2} = {7.5}^{2} - {4.5}^{2} \\ {de}^{2} = 56.25 - 20.25 = 36 \\ {de}^{2} = \sqrt{36} = 6[/tex]
[tex] \frac{bd}{ba} = \frac{be}{bc} = \frac{de}{ac} \\ \frac{bd}{ba} = \frac{de}{ac} \\ \frac{4.5}{10.8} = \frac{6}{ac} \\ ac = \frac{10.8 \times 6}{4.5} = 14.4 \\ [/tex]
- La théorème de Pythagore
- [tex] {bc}^{2} = {ba}^{2} + {ac}^{2} \\ {bc}^{2} = {10.8}^{2} + {14.4}^{2} \\ = 324 \\ bc = \sqrt{324 } = 18[/tex]
