Please helps me with … completing the square.
Did you try it? That is, are you stuck somewhere?
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complete the square examples and check out some of the (free) sites. If you have any questions about what you find, please post them here. Otherwise, try your exercise, using the same steps you studied in the worked examples. If you get stuck, please show us whatever steps you tried.
Hint: Write y instead of 0 (we can go back to y=0, after completing the square)
2a^2 + 4a + 5 = y
Before completing the square, we need positive one for the leading coefficient (i.e., the number multiplying the squared variable). In this equation, the leading coefficient is 2, instead of 1.
What can you do to each side of the equation, to obtain a^2 instead of 2a^2?