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If 2p + 3q = 17 and 2p + 2 - 3q + 1 = 5, then, find the value of p and q?

Correct Answer: 3, 2

Explanation:

Apply the law of Fractional Exponents and Laws of Exponents
(am) x (an) = am + n
a-m = 1/am
p0 = 1
and if pX = pY then X will be equal to Y. means X = Y;
(am)n = am x n
(am) x (an) = am + n
am ÷ an = am ? n
Or
am/an = am ? n
Given equation is
2p + 3q = 17 ----------------(i)
2p + 2 - 3q + 1 = 5
⇒ 2p x 22 - 3q x 3 = 5
⇒ 2p x 4 - 3q x 3 = 5
⇒ 4 x 2p - 3 x 3q = 5---------------(ii)
On multiplying Eq. (i) by 3 and adding it, with Eq. (ii), we get
3 x 2p + 3 x 3q = 51
4 x 2p - 3 x 3q = 5
_____________________________
7 x 2p = 56
⇒ 7 x 2p = 7 x 8
⇒ 2p = 8
⇒ 2p = 23
p = 3
On substituting the value of p in Eq. (i) . we get
23 + 3q = 17
⇒ 8 + 3q = 17
⇒ 3q = 17 - 8
⇒ 3q = 9
⇒ 3q = 32
q = 2


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