Question

2x2 + x + 5 = 0 i don’t know how to do this please help

Answer 1

9514 1404 393

Answer:

x = -0.25+√2.4375i or -0.25-√2.4375i

Explanation:

The quadratic formula works for this. The quadratic equation ...

ax² +bx +c = 0

has solutions given by the quadratic formula:

`x=(-b\pm√(b^2-4ac))/(2a)`

Your equation ...

2x² +x +5 = 0

has coefficients a=2, b=1, c=5, so the quadratic formula tells you the solutions are ...

`x=(-1\pm√(1^2-4\cdot2\cdot5))/(2\cdot2)=(-1\pm√(-39))/(4)\\\\x=\left\{-(1)/(4)+(√(39))/(4)i, -(1)/(4)-(√(39))/(4)i\right\}`

The decimal equivalents are ...

x = -0.25+√2.4375i or -0.25-√2.4375i . . . . . . the 'i' is outside the radical