SOLUTION: Find all the values of x (if any) where the tangent line to the graph of the given equation is horizontal. y = 4x^2 + 13x + 13 A. 6.5 B. -1.63 C. 0 D. 6.5 E. 1.63

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Find all the values of x (if any) where the tangent line to the graph of the given equation is horizontal. y = 4x^2 + 13x + 13 A. 6.5 B. -1.63 C. 0 D. 6.5 E. 1.63      Log On


   

Question 1118965: Find all the values of x (if any) where the tangent line to the graph of the given equation is horizontal.
y = 4x^2 + 13x + 13
A. 6.5
B. -1.63
C. 0
D. 6.5
E. 1.63
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Is this for Algebra 2, or for Calculus 1?

8x%5E1%2B13=0
Solve for x.

Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
.
Exactly at the vertex of the parabola: x = -b%2F%282a%29 = -13%2F%282%2A4%29 = -1.625.

Option B in your list.