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

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प्रश्न

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

2 +

बेरीज

उत्तर

Given, = 2x + 3, = `3/2` + 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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पाठ 10: Algebraic Expressions - Exercise [पृष्ठ ३२७]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 7
पाठ 10 Algebraic Expressions
Exercise | Q 89. (i) | पृष्ठ ३२७

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