Answer:
D) [tex](x + \frac{5}{2})^{2} = \frac{9}{4}[/tex]
Step-by-step explanation:
Step(i):-
Given equation
x² + 5 x + 8 = 4
⇒ [tex]x^{2} + 2 X \frac{5}{2} x + (\frac{5}{2} )^{2} - (\frac{5}{2} )^{2}+ 8 = 4[/tex]
Step(ii):-
By using (a + b)² = a² + 2 a b + b²
⇒ [tex](x + \frac{5}{2})^{2} - (\frac{5}{2} )^{2}+ 8 = 4[/tex]
⇒ [tex](x + \frac{5}{2})^{2} = 4 + (\frac{5}{2} )^{2} -8[/tex]
⇒ [tex](x + \frac{5}{2})^{2} = (\frac{25}{4} ) -4[/tex]
⇒ [tex](x + \frac{5}{2})^{2} = (\frac{25-16}{4} )[/tex]
⇒ [tex](x + \frac{5}{2})^{2} = \frac{9}{4}[/tex]
Final answer:-
[tex](x + \frac{5}{2})^{2} = \frac{9}{4}[/tex]