SOLUTION: Can someone explain how to solve the following problem with finding zeroes? f(x) = x^2+6x+5

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Can someone explain how to solve the following problem with finding zeroes? f(x) = x^2+6x+5      Log On


   

Question 275252: Can someone explain how to solve the following problem with finding zeroes?
f(x) = x^2+6x+5
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
The zeros are the x values that satisfy the equation x%5E2%2B6x%2B5=0


x%5E2%2B6x%2B5=0 Start with the given equation.


Notice that the quadratic x%5E2%2B6x%2B5 is in the form of Ax%5E2%2BBx%2BC where A=1, B=6, and C=5


Let's use the quadratic formula to solve for "x":


x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29 Start with the quadratic formula


x+=+%28-%286%29+%2B-+sqrt%28+%286%29%5E2-4%281%29%285%29+%29%29%2F%282%281%29%29 Plug in A=1, B=6, and C=5


x+=+%28-6+%2B-+sqrt%28+36-4%281%29%285%29+%29%29%2F%282%281%29%29 Square 6 to get 36.


x+=+%28-6+%2B-+sqrt%28+36-20+%29%29%2F%282%281%29%29 Multiply 4%281%29%285%29 to get 20


x+=+%28-6+%2B-+sqrt%28+16+%29%29%2F%282%281%29%29 Subtract 20 from 36 to get 16


x+=+%28-6+%2B-+sqrt%28+16+%29%29%2F%282%29 Multiply 2 and 1 to get 2.


x+=+%28-6+%2B-+4%29%2F%282%29 Take the square root of 16 to get 4.


x+=+%28-6+%2B+4%29%2F%282%29 or x+=+%28-6+-+4%29%2F%282%29 Break up the expression.


x+=+%28-2%29%2F%282%29 or x+=++%28-10%29%2F%282%29 Combine like terms.


x+=+-1 or x+=+-5 Simplify.


So the zeros are x+=+-1 or x+=+-5