Example 5 - Simplify the expressions and evaluate them as directed

Example 5 - Chapter 9 Class 8 Algebraic Expressions and Identities - Part 2
Example 5 - Chapter 9 Class 8 Algebraic Expressions and Identities - Part 3

  1. Chapter 9 Class 8 Algebraic Expressions and Identities
  2. Serial order wise

Transcript

Example 5 Simplify the expressions and evaluate them as directed: (i) ๐‘ฅ (๐‘ฅโˆ’3)+2 for ๐‘ฅ=1 ๐‘ฅ (๐‘ฅโˆ’3)+2=๐‘ฅร—๐‘ฅโˆ’๐‘ฅร—3+2 =๐‘ฅ^2โˆ’3๐‘ฅ+2 For x = 1 Putting x = 1 in expression ๐‘ฅ^2โˆ’3๐‘ฅ+2 = 1^2โˆ’3ร—1+2 = 1โˆ’3+2 = (1+2)โˆ’3 = 3โˆ’3 = ๐ŸŽ Example 5 Simplify the expressions and evaluate them as directed: (ii) 3๐‘ฆ(2๐‘ฆโˆ’7)โˆ’3(๐‘ฆโˆ’4)โˆ’63 for ๐‘ฆ=โˆ’2 3๐‘ฆ(2๐‘ฆโˆ’7)โˆ’3(๐‘ฆโˆ’4)โˆ’63 =3๐‘ฆร—2๐‘ฆโˆ’3๐‘ฆร—7โˆ’3ร—๐‘ฆ+3ร—4โˆ’63 =6๐‘ฆ^2โˆ’21๐‘ฆโˆ’3๐‘ฆ+12โˆ’63 =6๐‘ฆ^2โˆ’24๐‘ฆโˆ’51 For y = โˆ’๐Ÿ Putting ๐‘ฆ=โˆ’2 in expression 6๐‘ฆ^2โˆ’24๐‘ฆโˆ’51 = 6(โˆ’2)^2โˆ’24(โˆ’2)โˆ’51 =6ร—4+24ร—2โˆ’51 = 24+48โˆ’51 = 72โˆ’51 = ๐Ÿ๐Ÿ

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.