Examples
f(x)=x2+3x-3f(x)=x2+3x−3
Step 1
Step 1.1
Complete the square for x2+3x-3x2+3x−3.
Step 1.1.1
Use the form ax2+bx+cax2+bx+c, to find the values of aa, bb, and cc.
a=1a=1
b=3b=3
c=-3c=−3
Step 1.1.2
Consider the vertex form of a parabola.
a(x+d)2+ea(x+d)2+e
Step 1.1.3
Find the value of dd using the formula d=b2ad=b2a.
Step 1.1.3.1
Substitute the values of aa and bb into the formula d=b2ad=b2a.
d=32⋅1d=32⋅1
Step 1.1.3.2
Multiply 22 by 11.
d=32d=32
d=32d=32
Step 1.1.4
Find the value of ee using the formula e=c-b24ae=c−b24a.
Step 1.1.4.1
Substitute the values of cc, bb and aa into the formula e=c-b24ae=c−b24a.
e=-3-324⋅1e=−3−324⋅1
Step 1.1.4.2
Simplify the right side.
Step 1.1.4.2.1
Simplify each term.
Step 1.1.4.2.1.1
Raise 33 to the power of 22.
e=-3-94⋅1e=−3−94⋅1
Step 1.1.4.2.1.2
Multiply 44 by 11.
e=-3-94e=−3−94
e=-3-94e=−3−94
Step 1.1.4.2.2
To write -3−3 as a fraction with a common denominator, multiply by 4444.
e=-3⋅44-94e=−3⋅44−94
Step 1.1.4.2.3
Combine -3−3 and 4444.
e=-3⋅44-94e=−3⋅44−94
Step 1.1.4.2.4
Combine the numerators over the common denominator.
e=-3⋅4-94e=−3⋅4−94
Step 1.1.4.2.5
Simplify the numerator.
Step 1.1.4.2.5.1
Multiply -3−3 by 44.
e=-12-94e=−12−94
Step 1.1.4.2.5.2
Subtract 99 from -12−12.
e=-214e=−214
e=-214e=−214
Step 1.1.4.2.6
Move the negative in front of the fraction.
e=-214e=−214
e=-214e=−214
e=-214e=−214
Step 1.1.5
Substitute the values of aa, dd, and ee into the vertex form (x+32)2-214(x+32)2−214.
(x+32)2-214(x+32)2−214
(x+32)2-214(x+32)2−214
Step 1.2
Set yy equal to the new right side.
y=(x+32)2-214y=(x+32)2−214
y=(x+32)2-214y=(x+32)2−214
Step 2
Use the vertex form, y=a(x-h)2+ky=a(x−h)2+k, to determine the values of aa, hh, and kk.
a=1a=1
h=-32h=−32
k=-214k=−214
Step 3
Find the vertex (h,k)(h,k).
(-32,-214)(−32,−214)
Step 4