If 12x2 - ax + 7 = ax2 + 9x + 3 has only one (repeated) solution, then the positive integral solution of a is:
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Answer:
a = 3
Step-by-step explanation:
If 12x2 - ax + 7 = ax2 + 9x + 3 has only one (repeated) solution, then the positive integral solution of a is:
12x² - ax + 7 = ax² + 9x + 3
=> x²(12-a) - (9 + a) + 4 = 0
to have only one solution D = 0
(9 + a)² = 4(12-a)(4)
=> 81 + a² + 18a = 192 - 16a
=> a² + 34a - 111 = 0
=> a² + 37a - 3a - 111 = 0
=> a(a + 37) - 3(a + 37) = 0
=> (a -3)(a + 37) = 0
a = 3 & a = -37
-37 is not +v3
so a = 3
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