How do you find the x and y intercepts for #f(x) = -2x^2 + 4x + 3#?

1 Answer
Dec 29, 2015

The x-intercepts occur where #f(x) = 0 # and the y intercept occurs when #x = 0# giving #x = 1 -sqrt(10)/2# and # x = 1 + sqrt(10)/2# and #y=3#

Explanation:

The x-intercepts occur where #f(x) = 0 # and the y intercept occurs when #x = 0#
#x = 0 => F(x) = -2*0 +4*0 +3 = 3#
The y intercept is #y=3#
Use the quadratic formula to find the x intercepts as this equation does not factor straightforwardly.
#x = (-4 +- sqrt(16 - 4(-2)*3))/(-4)#
#x = 1 +- sqrt(40)/(-4)#
#x = 1 -sqrt(10)/2# or # x = 1 + sqrt(10)/2#