Question 976776
The general formula is:
{{{ y = a*x^2 + b*x + c }}}
( 0,3 )
{{{ 3 = a*0^2 + b*0 + c }}}
{{{ 3 = c }}}
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( 1,6 )
{{{ 6 = a*1^2 + b*1 + 3 }}}
{{{ a + b = 3 }}}
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( -1,8 )
{{{ 8 = a*(-1)^2 + b*(-1) + 3 }}}
{{{ a - b = 5 }}}
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Add the equations
{{{ a + b = 3 }}}
{{{ a - b = 5 }}}
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{{{ 2a = 8 }}}
{{{ a = 4 }}}
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{{{ a + b = 3 }}}
{{{ 4 + b = 3 }}}
{{{ b = -1 }}}
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The equation is:
{{{ y = 4x^2 - x + 3 }}}
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check:
( 0,3 )
{{{ y = 4x^2 - x + 3 }}}
{{{ 3 = 4*0^2 - 0 + 3 }}}
{{{ 3 = 3 }}}
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You can check the other 2 points