SOLUTION: Please solve tis equation: 8p^2+2p-15=0

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Question 596066: Please solve tis equation:
8p^2+2p-15=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

8p%5E2%2B2p-15=0 Start with the given equation.


Notice that the quadratic 8p%5E2%2B2p-15 is in the form of Ap%5E2%2BBp%2BC where A=8, B=2, and C=-15


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


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


p+=+%28-%282%29+%2B-+sqrt%28+%282%29%5E2-4%288%29%28-15%29+%29%29%2F%282%288%29%29 Plug in A=8, B=2, and C=-15


p+=+%28-2+%2B-+sqrt%28+4-4%288%29%28-15%29+%29%29%2F%282%288%29%29 Square 2 to get 4.


p+=+%28-2+%2B-+sqrt%28+4--480+%29%29%2F%282%288%29%29 Multiply 4%288%29%28-15%29 to get -480


p+=+%28-2+%2B-+sqrt%28+4%2B480+%29%29%2F%282%288%29%29 Rewrite sqrt%284--480%29 as sqrt%284%2B480%29


p+=+%28-2+%2B-+sqrt%28+484+%29%29%2F%282%288%29%29 Add 4 to 480 to get 484


p+=+%28-2+%2B-+sqrt%28+484+%29%29%2F%2816%29 Multiply 2 and 8 to get 16.


p+=+%28-2+%2B-+22%29%2F%2816%29 Take the square root of 484 to get 22.


p+=+%28-2+%2B+22%29%2F%2816%29 or p+=+%28-2+-+22%29%2F%2816%29 Break up the expression.


p+=+%2820%29%2F%2816%29 or p+=++%28-24%29%2F%2816%29 Combine like terms.


p+=+5%2F4 or p+=+-3%2F2 Simplify.


So the solutions are p+=+5%2F4 or p+=+-3%2F2