Solve by using the quadratic formula?

#3x^2+4x+10=0#

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2 Answers
Jun 18, 2018

See a solution process below:

Explanation:

The quadratic formula states:

For #color(red)(a)x^2 + color(blue)(b)x + color(green)(c) = 0#, the values of #x# which are the solutions to the equation are given by:

#x = (-color(blue)(b) +- sqrt(color(blue)(b)^2 - (4color(red)(a)color(green)(c))))/(2 * color(red)(a))#

Substituting:

#color(red)(3)# for #color(red)(a)#

#color(blue)(4)# for #color(blue)(b)#

#color(green)(10)# for #color(green)(c)# gives:

#x = (-color(blue)(4) +- sqrt(color(blue)(4)^2 - (4 * color(red)(3) * color(green)(10))))/(2 * color(red)(3))#

#x = (-color(blue)(4) +- sqrt(16 - 120))/6#

#x = (-color(blue)(4) +- sqrt(-104))/6#

#x = (-color(blue)(4) +- sqrt(4 xx -26))/6#

#x = (-color(blue)(4) +- sqrt(4)sqrt(-26))/6#

#x = (-color(blue)(4) +- 2sqrt(-26))/6#

Jun 18, 2018

No real solution.

Explanation:

The quadratic formular is #x= (-b+- sqrt(b^2-4ac))/(2a)# for the equation #color(red)(a)x^2+color(blue)(b)x+color(orange)(c)=0#

Therefore, in your case (#color(red)(3)x^2+color(blue)(4)x+color(orange)(10)=0#)
#a=color(red)(3)#
#b=color(blue)(4)#
#c=color(orange)(10)#

Using the formular, we get:
#x= (-color(blue)(4)+- sqrt(color(blue)(4)^2-4*color(red)(3)*color(orange)(10)))/(2*color(red)(3))#
#x= (-4+- sqrt(16-120))/(6)#
#x=-2/3+-sqrt(color(green)(-104))/6#

Since the radicand (#color(green)(-104)#) is negative, this equation has no real solutions for #x#.