What is the vertex form of y= x^2 + 5x + 6 y=x2+5x+6?

1 Answer
Jul 24, 2017

Vertex form is (x+5/2)^2-1/4(x+52)214.

Explanation:

Vertex from Standard Form

y=x^2+5x+6y=x2+5x+6 is the standard form for a quadratic equation, ax^2+bx+6ax2+bx+6, where a=1a=1, b=5b=5, and c=6c=6.

The vertex form is a(x-h)^2+ka(xh)2+k, and the vertex is (h,k)(h,k).

In the standard form, h=(-b)/(2a)h=b2a, and k=f(h)k=f(h).

Solve for hh and kk.

h=(-5)/(2*1)h=521

h=-5/2h=52

Now plug in -5/252 for xx in the standard form to find kk.

f(h)=k=(-5/2)^2+(5xx-5/2)+6f(h)=k=(52)2+(5×52)+6

Solve.

f(h)=k=25/4-25/2+6f(h)=k=254252+6

The LCD is 4.

Multiply each fraction by an equivalent fraction to make all of the denominators 44. Reminder: 6=6/16=61

f(h)=k=25/4-(25/2xx2/2)+(6/1xx4/4)f(h)=k=254(252×22)+(61×44)

Simplify.

f(h)=k=25/4-50/4+24/4f(h)=k=254504+244

Simplify.

f(h)=k=-1/4f(h)=k=14

Vertex (-5/2,-1/2)(52,12)

Vertex form: a(x-h)^2+ka(xh)2+k

1(x+5/2)^2-1/41(x+52)214

(x+5/2)^2-1/4(x+52)214