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| Question 486499:  1Find the vertex and focus of the parabola whose equation is 4y = x2 + 4.
 aV(0, 4), F(0, 3)
 bV(0, 1), F(0, 2)
 cV(4, 0), F(3, 0)
 dV(1, 0), F(2, 0)
 
 2Find the center and radius of the circle whose equation is x2 + 10x + y2 = 75.
 aC(10, 0), r = 100
 bC(10, 0), r = 10
 cC(5, 0), r = 100
 dC(5, 0), r = 10
 
 3Find the foci of the ellipse with the following equation.
 ((x-1)2÷9)+((Y+2)2÷25)=1
 aF1(5, 2), F2(3, 2)
 bF1(1, 2), F2(1, 6)
 cF1(4, 2), F2(2, 2)
 dF1(1, 1), F2(1, 5)
 
 4Find the slopes of the asymptotes of a hyperbola with the following equation.
 (Y2÷81)-(x2÷64)=1
 a8/9
 b9/8
 c8/9, 8/9
 d9/8, 9/8
 Answer by lwsshak3(11628)
      (Show Source): 
You can put this solution on YOUR website! 1Find the vertex and focus of the parabola whose equation is 4y = x2 + 4. 2Find the center and radius of the circle whose equation is x2 + 10x + y2 = 75.
 3Find the foci of the ellipse with the following equation.
 ((x-1)2÷9)+((Y+2)2÷25)=1
 4Find the slopes of the asymptotes of a hyperbola with the following equation.
 (Y2÷81)-(x2÷64)=1
 ***
 1) Find the vertex and focus of the parabola whose equation is 4y = x^2 + 4.
 y=x^2/4+4/4
 y=x^2/4+1
 y=(1/4)(x^2)+1
 x^2/4=y-1
 x^2=4(y-1)
 This is an equation of a parabola of standard form: (x-h)^2=4p(y-k), (h, k) being the (x, y) coordinates of the vertex. Parabola has a vertical axis of symmetry and it opens upwards.
 For given equation:
 vertex: (0,1)
 ..
 4p=4
 p=1
 focus: (0,2)
 ans:bV(0, 1), F(0, 2)
 ..
 2) Find the center and radius of the circle whose equation is x2 + 10x + y2 = 75.
 x^2+10x+y^2=75
 complete the square
 (x^2+10x+25)+(y^2)=75+25=100
 (x+5)^2+(y+0)^2=100
 center:(-5,0)
 radius=√100=10
 ans:dC(5, 0), r = 10
 ..
 3) Find the foci of the ellipse with the following equation.
 ((x-1)2/9)+((Y+2)2/25)=1
 This is an equation of an ellipse with vertical major axis of the standard form:
 (x-h)^2/b^2+(y-k)^2/a^2=1, a>b, with (h,k) being the (x,y) coordinates of the center.
 center: (1,-2)
 a^2=25
 b^2=9
 c^2=a^2-b^2=25-9=16
 c=√16=4
 Foci: (1,-2ħc)=(1,-2ħ4)=(1,2) and (1,-6)
 ans: bF1(1, 2), F2(1, 6)
 ..
 4Find the slopes of the asymptotes of a hyperbola with the following equation.
 (Y2/81)-(x2/64)=1
 This is an equation of a hyperbola with vertical transverse axis of the standard form:
 (y-k)^2/a^2-(x-h)^2/b^2=1, with (h,k) being the (x,y) coordinates of the center
 For given equation:
 Center: (0,0)
 a^2=81
 a=√81=9
 ..
 b^2=64
 b=√64=8
 slope of asymptotes=ħa/b=ħ9/8
 ans:
 d9/8, 9/8
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