Question #c5dd6

1 Answer
Jun 4, 2017

Answer:

#x=7/8+sqrt(32)/8, or 7/8-sqrt(32)/8#

Explanation:

Your question : #4x^2-7x-1=0#
This is a Quadratic Equation in the general form #ax^2+bx+c#
Therefore, we do not have to rearrange anything, we can go solve it right now. I'll solve this question by the Quadratic Formula because it can't be factorised.

The formula is this ; #(-b+-sqrt(b^2-4ac))/(2a)#

Our variables are as follows : #a=4, b=-7, c=-1#

Substitute the values

#(-(-7)+-sqrt((-7)^2-(4)(4)(-1)))/((2)(4)#

Simplify :

#(7+-sqrt(65))/8#

Simplify further ;

#7/8+sqrt(65)/8, 7/8-sqrt(65)/8#