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