10. What is the axis of symmetry for the parabola: y = − 2 ( x − 3 ) ( x − 7 )A) x=-2B) x=-3C) x=3D) x=511. Find the equation of a parabola in vertex form that passes through the point (7, 11) with vertex (5,-1)(A) y = 3 ( x − 5 ) 2 − 1(B) y = 1 12 ( x + 5 ) 2 − 1(C) y = − 3 ( x − 7 ) 2 + 11(D) y = 1 12 ( x + 7 ) 2 + 11

Question

10. What is the axis of symmetry for the parabola:   y  =  −  2  (  x  −  3  )  (  x  −  7  )A) x=-2B) x=-3C) x=3D) x=511. Find the equation of a parabola in vertex form that passes through the point (7, 11) with vertex (5,-1)(A)   y  =  3  (  x  −  5      )    2    −  1(B)   y  =      1    12    (  x  +  5      )    2    −  1(C)   y  =  −  3  (  x  −  7      )    2    +  11(D)   y  =      1    12    (  x  +  7      )    2    +  11

Paulina Horne · Accepted Answer

Solution:  y  =  −  2  (  x  −  3  )  (  x  −  7  )  y  =  −  2  (      x    2    −  7  x  −  3  x  +  21  )  y  =  −  2  (      x    2    −  10  x  +  21  )  y  =  −  2      x    2    +  20  x  −  42The x-coordinate of vertex given the symmetry of parabolaif (h,k) be the vertex of parabola then  h  =            −      b              2      a        =            −      20              2      (      −      2      )        =  5So axis of symmetry x=5

Databasex3 · Accepted Answer

General Eqn of parabola vertex form  y  =  a  (  x  −  h      )    2    +  kwhere (h,k) is vertex of parabolaGiven vertex=(5,-1)  ∵  y  =  a  (  x  −  5      )    2    −  1Given parabola passes through (7,11) therefore, these point weist satisfy the above Eqn  11  =  a  (  7  −  5      )    2    −  111=a(4)-112=4aa=3So Eqn.  y  =  3  (  x  −  5      )    2    −  1 Answer

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