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  1. If 2a + 3b = 17 and 2a + 2 - 3b +1 = 5, then
    1. a = 2, b = 3
    2. a = -2, b = 3
    3. a = 2, b = -3
    4. a = 3, b = 2
Correct Option: D

Given, 2a + 3b = 17
and 2a + 2 - 3b + 1 = 5
⇒ 22 x 22 - 3b x 31 = 5
⇒ 4.2a - 3.3b = 5
Let 2a = x amd 3b = y
Then, x + y = 17 ...(i)
4x - 3y = 5 ...(ii)
On multiplying Eq. (i) by 3 and adding to Eq (ii), we get
3x + 3y = 51
4x - 3y = 5
------------------
7x = 56
⇒ x = 8

On putting the value of x in Eq. (i), we get
8 + y = 17
∴ y = 9

Now, 2a = x
⇒ 2a = 8 (2)3
∴ 3b = y = 9
⇒ 3b = 32
∴ b = 2
Hence, a = 3 and b = 2



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