Question

2x squares plus 5x plus 9 equals 0 using quadratic formula

Answer 1

Answer:

x = -$\frac{5}{4}$  + $\frac{\sqrt{47} }{2}$ i   or     -$\frac{5}{4}$  -  $\frac{\sqrt{47} }{2}$ i

x  = -1.25 + 3.43 i     or   - 1.25 - 3.43 i

Step-by-step explanation:

solve 2x² + 5x + 9 = 0  using quadratic formula

The quadratic formula is;

x = -b ±√b² - 4ac   / 2a

a = 2       b = 5    and     c= 9

We can now proceed to insert the values into the formula;

x = -5 ± √5² - 4(2)(9)   /   2(2)

x = -5±√25 -72  /  4

x = -5 ± √-47   / 4

x = -$\frac{5}{4}$  ±$\sqrt{\frac{47}{4} }$ . $\sqrt{-1}$

But $\sqrt{-1}$ = i

x = -$\frac{5}{4}$  ±$\sqrt{\frac{47}{4} }$ . i

 =-$\frac{5}{4}$  ± $\frac{\sqrt{47} }{2}$ i

x = -$\frac{5}{4}$  + $\frac{\sqrt{47} }{2}$ i   or     -$\frac{5}{4}$  -  $\frac{\sqrt{47} }{2}$ i

x  = -1.25 + 3.43 i     or   - 1.25 - 3.43 i