Question

1) Find the vlaue of 9a2 + 1662, if 3a + 4b = 9 and ab = 21.

2) Find the value of 49x2 + 36y2, if 7x - y = 11 and xy =

1) 9a² + 16b²
3a+ 4b=9
squaring on both sides
(3a+4b)=9
9a²+16b²+2×3×4×a×b= 81
9a²+16b²+ 24×21= 81

9a²+16b²+504=81
9a²+16b²+504 -81
Hence , -423

2) 49x²+36y²
7x-6y =11
Xy =1
49x²+36+ 84xy -8xy
( 49x²+ 36y²-84xy )+8xy
( 7x -6y)²+84xy
( 11)²84 ×1
( 121 +84 )
Hence, 205


Hope it help you
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Answer 1

Answer:

1) 162. 9a2 + 16b2 + 24ab = 256. 9a2 + 16b2 + 24 x 4 = 256 .

2) 205

Step-by-step explanation: