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If = 2x + 3, = 32x+7 and = x – 3 then find the value of: 12 + – 3

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Question

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

`1/2` + – 3

Sum
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Solution

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

`1/2` + – 3 = `1/2(3/2 xx 2 + 7) + (8 - 3) - 3(2 xx 0 + 3)`

= `1/2(10) + 5 - 3(3)`

= 5 + 5 – 9

= 1

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Chapter 10: Algebraic Expressions - Exercise [Page 327]

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NCERT Exemplar Mathematics [English] Class 7
Chapter 10 Algebraic Expressions
Exercise | Q 89. (ii) | Page 327

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