Find the value of 4x2 + y2 + 25z2 + 4xy – 10yz – 20zx when x = 4, y = 3 and z = 2. -Maths 9th

Find the value of 4x2 + y2 + 25z2 + 4xy – 10yz – 20zx when x = 4, y = 3 and z = 2. -Maths 9th
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4x²+y²+25z²+4xy-10yz-20zx when x=4, y=3 &z=2 so =>4(4)²+(3)²+ 25(2)²+4(4)(3)-10(3)(2)-20(2)(4) =>64+9+100+48-60-160 =>221-220 =>1
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