How do you solve x^2 + 3x - 5 = 0?

1 Answer
Nov 1, 2015

x = (-3 + sqrt29)/2 or x = (-3 - sqrt29)/2

Explanation:

This equation does not easily factorise so using the general equation y = ax^2 + bx +c and the formula

x =( -b +sqrt( b^2 - 4ac))/(2a) or x =( -b - sqrt(b^2 - 4ac))/(2a)

then if y = x^2 +3x-5

a =1, b = 3 and c = -5

x =( -3 + sqrt(3^2 - (-20)))/2 or x = (-3 - sqrt(3^2 - (-20)))/2

which comes to the given answer.
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