Quiz Maths 9ème : Équations, Géométrie et Fonctions

Question 1 sur 10 10:00

[{"id":62512,"question":"Quelle est la solution de l'équation 3x + 5 = 20 ?","option_a":"x = 5","option_b":"x = 15","option_c":"x = 7","option_d":"x = 10","option_e":"","option_f":"","bonne_reponse":"A","explication":"Pour résoudre 3x + 5 = 20, soustrayez 5 des deux côtés : 3x = 15. Divisez ensuite par 3 : x = 5.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62513,"question":"Un triangle isocèle a deux angles égaux à 40°. Quelle est la mesure du troisième angle ?","option_a":"100°","option_b":"80°","option_c":"60°","option_d":"40°","option_e":"","option_f":"","bonne_reponse":"B","explication":"La somme des angles d'un triangle est 180°. Si deux angles valent 40°, le troisième est 180° - 40° - 40° = 100°.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62514,"question":"La fonction f(x) = 2x + 3 est une fonction affine.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"Une fonction affine s'écrit sous la forme f(x) = ax + b. Ici, a = 2 et b = 3, donc c'est bien une fonction affine.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62515,"question":"Quel est le résultat de (-3)² ?","option_a":"9","option_b":"-9","option_c":"6","option_d":"-6","option_e":"","option_f":"","bonne_reponse":"A","explication":"(-3)² = (-3) × (-3) = 9. Attention à ne pas confondre avec -3² qui vaut -9.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62516,"question":"Un carré a une aire de 64 cm². Quelle est la longueur de son côté ?","option_a":"8 cm","option_b":"16 cm","option_c":"4 cm","option_d":"32 cm","option_e":"","option_f":"","bonne_reponse":"A","explication":"L'aire d'un carré est côté × côté. Si l'aire est 64 cm², alors côté = √64 = 8 cm.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62517,"question":"La somme des angles d'un quadrilatère convexe est toujours 360°.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"Un quadrilatère convexe peut être divisé en deux triangles, chacun ayant une somme d'angles de 180°. Donc 2 × 180° = 360°.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62518,"question":"Résolvez l'équation 2(x - 4) = 3x + 1.","option_a":"x = -9","option_b":"x = 9","option_c":"x = -3","option_d":"x = 3","option_e":"","option_f":"","bonne_reponse":"A","explication":"Développez d'abord : 2x - 8 = 3x + 1. Soustrayez 2x des deux côtés : -8 = x + 1. Soustrayez 1 : x = -9.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62519,"question":"Un cercle a un rayon de 5 cm. Quelle est sa circonférence ?","option_a":"10π cm","option_b":"25π cm","option_c":"5π cm","option_d":"20π cm","option_e":"","option_f":"","bonne_reponse":"A","explication":"La circonférence d'un cercle est 2πr. Ici, r = 5 cm, donc circonférence = 2π × 5 = 10π cm.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62520,"question":"La fonction f(x) = x² est une fonction linéaire.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"B","explication":"Une fonction linéaire s'écrit sous la forme f(x) = ax. Ici, f(x) = x² est une fonction du second degré, pas linéaire.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":62521,"question":"Quel est le pourcentage de 25 sur 200 ?","option_a":"12,5%","option_b":"15%","option_c":"20%","option_d":"25%","option_e":"","option_f":"","bonne_reponse":"A","explication":"Pour calculer un pourcentage, divisez la partie par le tout et multipliez par 100 : (25 \/ 200) × 100 = 12,5%.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0}]