How do you find the vertex and the intercepts for #y=x^2-10x+20#?

1 Answer
Jul 26, 2016

Vertex is at #(5,-5) # y-intercept is at #(0,20)# x-intercepts are at #(2.764,0) and (7.236,0)#

Explanation:

#y=x^2-10x+20 = (x-5)^2 -25+20 =(x-5)^2-5 :.#Comparing with vertex form of equation; #y=a(x-h)^2+k# we get vertex at #(h,k)=(5,-5)#.To get y-intercept putting x=0 in the equation we get #y=20# and to find x-intercepts putting y=0 in the equation we get #(x-5)^2-5=0 or (x-5)^2 =5 or (x-5) = +-sqrt5 or x= 5+-sqrt5 or x= 2.764,7.236 :.#Vertex is at #(5,-5) # y-intercept is at #(0,20)# x-intercepts are at #(2.764,0) and (7.236,0)# graph{x^2-10x+20 [-40, 40, -20, 20]}[Ans]