SOLUTION: 5y2-8y=2 use the quadratic formula

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Question 457063: 5y2-8y=2 use the quadratic formula
Found 2 solutions by MathLover1, poliphob3.14:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

5y%5E2-8y=2
5y%5E2-8y-2=0
y=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+...notice that a=5, b=-8, and c=-2

y=+%28-%28-8%29+%2B-+sqrt%28+%28-8%29%5E2-4%2A5%2A%28-2%29+%29%29%2F%282%2A5%29+


y=+%288+%2B-+sqrt%28+64%2B40+%29%29%2F10+

y=+%288+%2B-+10.2%29%2F10+

solutions:

y=+%288+%2B+10.2%29%2F10+

y=++18.2%2F10+
y=++1.82+

or
y=+%288+-+10.2%29%2F10+

y=++-2.2%2F10+

y=++-0.22+

Answer by poliphob3.14(115) About Me  (Show Source):
You can put this solution on YOUR website!
First set the equation equal to zero:5y%5E2-8y-2=0, using the quadratic formula we get:
y=%288%2B-sqrt%288%5E2%2B4%2A5%2A2%29%29%2F%282%2A5%29=%288%2B-sqrt%28104%29%29%2F10, reduce the fraction.
The roots are: y=%284%2Bsqrt%2826%29%29%2F5 and y=%284-sqrt%2826%29%29%2F5