SOLUTION: Find the vertex of the parabola: f(x)=3x^2-24x+43

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Question 269455: Find the vertex of the parabola:
f(x)=3x^2-24x+43
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
step 1 - factor out the 3 from the first 2 terms to get
y+=+3%28x%5E2+-+8x%29+%2B+43
step 2 - draw lines after the -8x and the 43. These are number holders. numbers will go here.
y+=+3%28x%5E2+-+8x+%2B+_____%29+%2B+43+%2B+_____+
step 3 - take 1/2 of the -8 and square it to get (-4)^2. Put this in the parenthesis to get
y+=+3%28x%5E2+-+8x+%2B+%28-4%29%5E2%29+%2B+43+%2B+_____+
step 4 - you have put 16 into the (__) information, but there is a 3 on the outside. Multiply 3 by 16 to get 48. We have just added 48 to the right. To keep it all balanced, put -48 in the outside blank space. We get
y+=+3%28x%5E2+-+8x+%2B+%28-4%29%5E2%29+%2B+43+%2B+-48+
step 5 - rewrite the trinomial as a binomial squared and simplify the outside numbers as
y+=+3%28x+-4%29%5E2+-5+
step 6 state vertex as
(h,k) = (4,-5)