If 217x + 131y = 913, 131x + 217y = 827, then x + y is
(a) 5 (b) 6 (c) 7 (d) 8

CBSE Class 10 Sample Paper for 2022 Boards - Maths Standard [MCQ]
CBSE Class 10 Sample Paper for 2022 Boards - Maths Standard [MCQ]
Last updated at Dec. 16, 2024 by Teachoo
Transcript
Question 24 If 217𝑥 + 131𝑦 = 913, 131𝑥 + 217𝑦 = 827, then 𝑥 + 𝑦 is (a) 5 (b) 6 (c) 7 (d) 8Given equations 217𝑥 + 131𝑦 = 913 …(1) 131𝑥 + 217𝑦 = 827 …(2) Adding both equations (1) and (2) (217𝒙 + 131𝒚) + (131𝒙 + 217𝒚) = 913 + 827 (217𝑥 + 131𝑥) + (131𝑦 + 217𝑦) = 1740 348𝑥 + 348𝑦 = 1740 348 (𝒙 + 𝒚) = 1740 𝑥 + 𝑦 = 1740/348 𝑥 + 𝑦 = 5 So, the correct answer is (a)