Question

the value of 9x²+4y²+I+12xy+4yz+6xy for x=2,y=2 and z=1 is


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Answer 1

Answer:

$9 {x}^{2} + 4 {y}^{2} + 12xy + 4yz + 6xy \\ = 9 {x}^{2} + 4 {y}^{2} + 18xy + 4yz \\ = 9 \times {2}^{2} + 4 \times {2}^{2} + 18 \times 2 \times 2 + 4 \times 2 \times 1 \\ = 9 \times 4 + 4 \times 4 + 72 + 8 \\ = 36 + 16 + 80 \\ = 132$