How do you solve the quadratic equation #4x^2 - 8x + 1= 0# by using the Quadratic Formula?

2 Answers
Apr 10, 2016

Answer:

Using quadratic formula: #(-b+-sqrt(b^2-4ac))/(2a)#

Explanation:

you assume the value
=> 4 to be your ''a''
=> -8 to be your ''b''
=> 1 to be your ''c''

Now just replace the values in the formula, and obtain your two values

-> N.B You will obtain two values (might be one positive one and the other, a negative one)

Apr 10, 2016

Answer:

#x=(2+-sqrt3)/2#

Explanation:

#color(blue)(4x^2-8x+1=0#

This is a Quadratic equation (in form #ax^2+bx+c=0#)

Use Quadratic equation

#color(brown)(x=(-b+-sqrt(b^2-4ac))/(2a)#

Note: #aandb# are the coefficients of #x^2and x# and #c# is the constant number

So,

#color(purple)(a=4,b=-8,c=1#

#rarrx=(-(-8)+-sqrt(-8^2-4(4)(1)))/(2(4))#

#rarrx=(8+-sqrt(64-(16)))/(8)#

#rarrx=(8+-sqrt(48))/(8)#

#rarrx=(8+-sqrt(16*3))/(8)#

#rarrx=(8+-4sqrt3)/8#

#rarrx=(cancel8^2+-cancel4^1sqrt3)/cancel8^2#

#color(green)(rArrx=(2+-sqrt3)/2#

Remember that #+-# means "plus or minus"

Which implies that

#color(indigo)(x=((2+sqrt3)/(2),(2-sqrt3)/(2))#

If you are a bit confused with the Quadratic formula

Watch this video