If one root of the quadratic equation 3x 2 + px + 4 = 0 is 2/3, then find
the value of p and the other root of the equation.

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  1. Class 10
  2. Solutions of Sample Papers for Class 10 Boards

Transcript

Question 28 (Choice - 1) If one root of the quadratic equation 3x2 + px + 4 = 0 is 2/3, then find the value of p and the other root of the equation.Since one root is 2/3 Putting ๐Ÿ/๐Ÿ‘ in equation 3x2 + px + 4 = 0 3(2/3)^2+๐‘ ร—2/3+4=0 3 ร—4/9+๐‘ ร—2/3+4=0 4/3+๐‘ ร—2/3+4=0 4/3+4+ ๐‘ ร—2/3=0 (4 + 16)/3+ ๐‘ ร—2/3=0 20/3+ ๐‘ ร—2/3=0 ๐‘ ร—2/3=โˆ’20/3 ๐‘ =โˆ’20/3 ร—3/2 ๐’‘ = โˆ’10 Thus, our equation becomes 3x2 + px + 4 = 0 3x2 โˆ’ 10x + 4 = 0 Now, Product of Roots = ๐Ÿ’/๐Ÿ‘ First Root ร— Second Root = 4/3 2/3 ร— Second Root = 4/3 Second Root = 4/3 ร—3/2 Second Root = 2

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.