Quiz Maths 9ème : Équations, Fonctions et Géométrie

Question 1 sur 10 10:00

[{"id":42276,"question":"Quelle est la solution de l'équation 3x - 5 = 10 ?","option_a":"x = 5","option_b":"x = 15\/3","option_c":"x = 5\/3","option_d":"x = 15","option_e":"","option_f":"","bonne_reponse":"A","explication":"Pour résoudre 3x - 5 = 10, on ajoute 5 des deux côtés : 3x = 15, puis on divise par 3 : x = 5.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42277,"question":"L'inéquation 2x + 7 \u003E 15 a pour solution x \u003E 4.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"En soustrayant 7 : 2x \u003E 8, puis en divisant par 2 : x \u003E 4. L'affirmation est donc vraie.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42278,"question":"Quelle est l'image de 2 par la fonction f(x) = 3x² - 5 ?","option_a":"f(2) = 7","option_b":"f(2) = 12","option_c":"f(2) = -5","option_d":"f(2) = 19","option_e":"","option_f":"","bonne_reponse":"B","explication":"En remplaçant x par 2 : f(2) = 3*(2)² - 5 = 3*4 - 5 = 12 - 5 = 7. La bonne réponse est f(2) = 7.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42279,"question":"Le théorème de Pythagore s'applique uniquement aux triangles rectangles.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"Le théorème de Pythagore stipule que dans un triangle rectangle, le carré de l'hypoténuse est égal à la somme des carrés des deux autres côtés. Il ne s'applique donc qu'aux triangles rectangles.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42280,"question":"Quelle est la forme développée de (x + 3)(x - 2) ?","option_a":"x² + x - 6","option_b":"x² + 5x - 6","option_c":"x² - 6","option_d":"x² + x + 6","option_e":"","option_f":"","bonne_reponse":"A","explication":"En développant : (x + 3)(x - 2) = x² - 2x + 3x - 6 = x² + x - 6.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42281,"question":"Si deux droites sont parallèles, alors leurs coefficients directeurs sont égaux.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"Deux droites parallèles ont des coefficients directeurs identiques, car elles ne se croisent jamais et ont la même pente.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42282,"question":"Résoudre l'inéquation -4x + 8 ≤ 20.","option_a":"x ≥ -3","option_b":"x ≤ -3","option_c":"x ≥ 3","option_d":"x ≤ 3","option_e":"","option_f":"","bonne_reponse":"A","explication":"En soustrayant 8 : -4x ≤ 12, puis en divisant par -4 (attention au changement de sens) : x ≥ -3.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42283,"question":"Le point A(2 ; -3) appartient-il à la droite d'équation y = 2x - 7 ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"B","explication":"En remplaçant x par 2 : y = 2*2 - 7 = 4 - 7 = -3. Le point A(2 ; -3) appartient bien à la droite.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42284,"question":"Quelle est la valeur de x dans l'équation 5(x + 2) = 3x + 20 ?","option_a":"x = 5","option_b":"x = -5","option_c":"x = 10","option_d":"x = 0","option_e":"","option_f":"","bonne_reponse":"A","explication":"En développant : 5x + 10 = 3x + 20. En soustrayant 3x : 2x + 10 = 20. En soustrayant 10 : 2x = 10. Donc x = 5.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":42285,"question":"Le triangle ABC avec AB = 5 cm, BC = 12 cm et AC = 13 cm est rectangle en B.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"Vérifions avec le théorème de Pythagore : AB² + BC² = 5² + 12² = 25 + 144 = 169, et AC² = 13² = 169. L'égalité est vérifiée, donc le triangle est rectangle en B.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0}]