Question 1096796
1, -4, 9, -16, 25, 
<pre>
1² = 1×1 = 1,  keep the positive sign, 1

2² = 2×2 = 4,  change the sign to -4

3² = 3×3 = 9,  keep the positive sign, 9

4² = 4×4 = 16  change the sign to -16

5² = 5×5 = 25  keep the positive sign, 25

So what's the answer?

Edwin</pre>