TS Polycet (Polytechnic) 2018 Previous Question Paper with Answers And Model Papers With Complete Analysis

11)If = 5 and =6 , then x, y is …………………

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B) (14,9)
Explanation:= 5
⇒ = 5
⇒ 3x+7y = 105
=6
=6
9x – 2y = 108 …………….(1)
3(3x + 7y = 105) = 9x + 21y = 315 …………….(2)
by solving (1) and (2)
9x — 2y= 108
9x + 21y = 315
(-) (-) (-)
____________
-23y = -207
Y = 9
Now substitute y = 9 in 3x + 7y = 105
3x + 7 x 9 = 105
⇒ 3x + 63 = 105
⇒ 3x = 105 – 63 = 42
⇒ x = 14
∴ x = 14 and y = 9

12)The graph of y + x² = 0 lies in the quadrants

13)Solution of the equations √2x + √3y = 0 and √3x – √8y = 0 is ………………………

14)If 2^X + 3^y = 17 and 2^{X + 2} – 3^{y + 1} = 5, then y = …………………….

15)x + y = 2015 has ….. number of solutions.

16)The condition for a x² + bx + c = 0 to be a quadratic equation is

17)The difference between two consecutive positive integers is

18)If α,β are the roots of ax² + bx + c = 0, then 1/α + 1/β =

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A) –b/c
Explanation:1/α + 1/β =
=
= -b/c

19)If 65 diagonals are drawn to a polygon of ‘n’ sides, then what is the value of ‘n’?

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C) 13
Explanation:No. of sides of polygon = n
No. of diagonal of a polygon having ‘n’ sides =
= 65 ⇒ n² – 3n = 130
⇒ n²-3n-130 = 0 ⇒ n² + 10n-13n-130=0
⇒ n (n + 10) – 13 (n + 10) =0
⇒ (n + 10) (n – 13) = 0 ⇒ n = 13
∴ No. of sides are n = 13

20)Find the 10th term in A.P. 5, 1, -3, -7,…………….