How do you find the vertex and the intercepts for y = (x + 5)^2 +2?

1 Answer
Mar 19, 2017

vertex: (-5, 2)
no x-intercepts
y-intercept: (0, 27)

Explanation:

Standard form used for graphing a parabola: y = a(x-h)^2+k,
where vertex:(h, k)

Finding the vertex:
Since the function y = (x+5)^2 + 2 is in standard form, you can easily find the vertex to be (-5, 2).

Finding x-intercepts by letting y = 0:
1. Distribute the function: y = x^2+5x + 5x +25+2
2. Add like terms: y = x^2 + 10x + 27
3. Factor or use the quadratic formula x =( -B+- sqrt(B^2-4AC))/(2A)
x = (-10+- sqrt(100-4*1*27))/2 = (-10+-sqrt(-8))/2 = -5 +-sqrt(2)i

No real solutions, only complex solutions. This means the function does not touch the x-axis. No x-intercepts

Finding y-intercepts: by letting x = 0:
y = 5^2 + 2 = 27
y-intercept: (0, 27)