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)#