Question

Can someone help me with the last one on the second row? http://prntscr.com/8pjizy

Answer 1

y-5=-2(x+1)^2
\[y=5-2\left( x+1 \right)^2=\left( \sqrt{5} \right)^2-\left\{ \sqrt{2}\left( x+1 \right) \right\}^2\]
\[y=\left\{ \sqrt{5}+\sqrt{2}\left( x+1 \right) \right\}\left\{ \sqrt{5}-\sqrt{2}\left( x+1 \right) \right\}\]
\[or ~y=-\left( \sqrt{2}x+\sqrt{2}+\sqrt{5} \right)\left( \sqrt{2}x+\sqrt{2} -\sqrt{5}\right)\]

Answer 2

furthermore, if we develop the square of binomial at the rifght side, we can write this:
\[y = 5 - 2{x^2} - 2 - 4x = ...?\]
please complete the computation above

Answer 3

right* side