Video narration
Is prashn mein anant halon ki shart lagani hai. Teesri equation, pehli do equations ka aisa linear combination honi chahiye jo consistent bhi rahe. Yani variables ke coefficients ke saath daahini taraf ka constant bhi usi combination se mile. Maan lein teesri equation, pehli equation ko alpha aur doosri ko beta se guna karke jodne par milti hai. x aur y ke coefficients milane par alpha + 2 beta = 1, aur 5 alpha + 3 beta = 6. In dono ko hal karne se alpha = 9/7 aur beta = -1/7 milta hai. Ab z ka coefficient milaen: a = 6 alpha + 4 beta, isliye a = 50/7. Constant bhi usi tarah milana zaroori hai: b = 4 alpha + 7 beta = 29/7. Atah a - b = 50/7 - 29/7 = 3. Isliye aavashyak sambandh a - b = 3 hai. Diye gaye vikalpon mein yahi sambandh option (a) mein hai; agar option (b) par bhi yahi chhapa hai, to dono vikalpon mein chhapai dohrayi gayi hai.