If = 2x + 3, = 32x+7 and = x – 3 then find the value of: 2 + – - Mathematics

Question

If = 2x + 3, = `3/2x + 7` and = x – 3 then find the value of:

² + –

Sum

Solution

Given, = 2x + 3, = `3/2x + 7` and = x – 3

² + – = `2 xx (2 xx 6 + 3) + (3/2 xx 3 + 7) - (1 - 3)`

= `2 xx (12 + 3) + (9/2 + 7) - (-2)`

= `2 xx 15 + (23/2) + 2`

= `30 + 2 + 23/2`

= `32 + 23/2`

= `(32 xx 2 + 23)/2`

= `(64 + 23)/2`

= `87/2`

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Q 89. (i)Q 88. (c)Q 89. (ii)

Chapter 10: Algebraic Expressions - Exercise [Page 327]

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NCERT Exemplar Mathematics [English] Class 7

Chapter 10 Algebraic Expressions
Exercise | Q 89. (i) | Page 327

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