Question 1120242
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factorise x^2+4y^216z^2+4xy+16yz+8zx and find the value when x=2, y=-1 and z=1
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First, &nbsp;your expression is written &nbsp;<U>INCORRECTLY</U>.


The correct form is &nbsp;<U>THIS</U>:


<pre>
    factorize  x^2 + 4y^2 + 16z^2 + 4xy + 16yz + 8zx and find the value when x=2, y=-1 and z=1
</pre>

Then


<pre>
    x^2 + 4y^2 + 16z^2 + 4xy + 16yz + 8zx = {{{(x + 2y + 4z)^2}}},


and it answers the first question.


To answer the second questions, substitute the values into the right side of the formula. You will get


    {{{(x + 2y + 4z)^2}}} = {{{(2 - 2*1 + 4*1)^2}}} = {{{4^2}}} = 16.
</pre>

Solved.