Question

factorise 9x2+12ax-y2-2yz+4a2

Answer 1

You mean,
$9 {x}^{2} + 12ax - {y}^{2} - 2yz + 4 {a}^{2}$
First, we will arrange the like terms,
$(9 {x}^{2} + 12ax + 4 {a}^{2} ) - {y}^{2} - 2yz$
Now we will add two terms,
$(9 {x}^{2} + 12ax + {4a}^{2} ) - {y}^{2} - 2yz - {z}^{2} + {z}^{2}$
Ans,
${(3x + 2a)}^{2} - {(y + z)}^{2} - {z}^{2}$

I hope this helps.
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