Algebra Examples
f(x)=7x2+5x-4
Step 1
Step 1.1
Complete the square for 7x2+5x-4.
Step 1.1.1
Use the form ax2+bx+c, to find the values of a, b, and c.
a=7
b=5
c=-4
Step 1.1.2
Consider the vertex form of a parabola.
a(x+d)2+e
Step 1.1.3
Find the value of d using the formula d=b2a.
Step 1.1.3.1
Substitute the values of a and b into the formula d=b2a.
d=52⋅7
Step 1.1.3.2
Multiply 2 by 7.
d=514
d=514
Step 1.1.4
Find the value of e using the formula e=c-b24a.
Step 1.1.4.1
Substitute the values of c, b and a into the formula e=c-b24a.
e=-4-524⋅7
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 5 to the power of 2.
e=-4-254⋅7
Step 1.1.4.2.1.2
Multiply 4 by 7.
e=-4-2528
e=-4-2528
Step 1.1.4.2.2
To write -4 as a fraction with a common denominator, multiply by 2828.
e=-4⋅2828-2528
Step 1.1.4.2.3
Combine -4 and 2828.
e=-4⋅2828-2528
Step 1.1.4.2.4
Combine the numerators over the common denominator.
e=-4⋅28-2528
Step 1.1.4.2.5
Simplify the numerator.
Step 1.1.4.2.5.1
Multiply -4 by 28.
e=-112-2528
Step 1.1.4.2.5.2
Subtract 25 from -112.
e=-13728
e=-13728
Step 1.1.4.2.6
Move the negative in front of the fraction.
e=-13728
e=-13728
e=-13728
Step 1.1.5
Substitute the values of a, d, and e into the vertex form 7(x+514)2-13728.
7(x+514)2-13728
7(x+514)2-13728
Step 1.2
Set y equal to the new right side.
y=7(x+514)2-13728
y=7(x+514)2-13728
Step 2
Use the vertex form, y=a(x-h)2+k, to determine the values of a, h, and k.
a=7
h=-514
k=-13728
Step 3
Find the vertex (h,k).
(-514,-13728)
Step 4