SOLUTION: How do I break down the problem and solve it, 3x^2+19x-14=0 using the Quadratic Equation?

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Question 150810This question is from textbook Blitzer (college Algebra
: How do I break down the problem and solve it, 3x^2+19x-14=0 using the Quadratic Equation? This question is from textbook Blitzer (college Algebra

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
From 3x%5E2%2B19x-14, we can see that a=3, b=19, and c=-14


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


x+=+%28-%2819%29+%2B-+sqrt%28+%2819%29%5E2-4%283%29%28-14%29+%29%29%2F%282%283%29%29 Plug in a=3, b=19, and c=-14


x+=+%28-19+%2B-+sqrt%28+361-4%283%29%28-14%29+%29%29%2F%282%283%29%29 Square 19 to get 361.


x+=+%28-19+%2B-+sqrt%28+361--168+%29%29%2F%282%283%29%29 Multiply 4%283%29%28-14%29 to get -168


x+=+%28-19+%2B-+sqrt%28+361%2B168+%29%29%2F%282%283%29%29 Rewrite sqrt%28361--168%29 as sqrt%28361%2B168%29


x+=+%28-19+%2B-+sqrt%28+529+%29%29%2F%282%283%29%29 Add 361 to 168 to get 529


x+=+%28-19+%2B-+sqrt%28+529+%29%29%2F%286%29 Multiply 2 and 3 to get 6.


x+=+%28-19+%2B-+23%29%2F%286%29 Take the square root of 529 to get 23.


x+=+%28-19+%2B+23%29%2F%286%29 or x+=+%28-19+-+23%29%2F%286%29 Break up the expression.


x+=+%284%29%2F%286%29 or x+=++%28-42%29%2F%286%29 Combine like terms.


x+=+2%2F3 or x+=+-7 Simplify.


So our answers are x+=+2%2F3 or x+=+-7