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45 votes
45 votes
NO LINKS!! Please help me. Part 2​

NO LINKS!! Please help me. Part 2​-example-1
User Aron Asztalos
by
2.4k points

2 Answers

14 votes
14 votes

We need equation of the parabolas

#1

  • Vertex is at (6,4)

One x intercept is present (4,0)

Now put that in vertex form of parabola

  • y=a(x-h)²+k
  • 0=a(4-6)²+4
  • 4a+4=0
  • a=-1

So

equation

  • y=-(x-6)²+4

#2

  • Vertex at (-5,0)

So equation

  • y=a(x+5)²+0=a(x+5)²

See the general quadratic equation having vertex (0,0) is shifted to (-5,0) means 5 units left .

So there is no a means a=

Equation remains same

  • y=(x+5)²
User Anthony Nandaa
by
2.8k points
19 votes
19 votes

Answer:

11)
y=-(x-6)^2+4

12)
y=(x+5)^2

Explanation:

Vertex form of a parabola:


y=a(x-h)^2+k where (h, k) is the vertex

Question 11

From inspection of the graph, the vertex is (6, 4)


\implies y=a(x-6)^2+4

To find
a, substitute the coordinates of a point on the curve into the equation.

Using point (4, 0):


\implies a(4-6)^2+4=0


\implies a(-2)^2+4=0


\implies 4a=-4


\implies a=-1

Therefore, the equation of the parabola in vertex form is:


y=-(x-6)^2+4

Question 12

From inspection of the graph, the vertex is (-5, 0)


\implies y=a(x+5)^2

To find
a, substitute the coordinates of a point on the curve into the equation.

Using point (-3, 4):


\implies a(-3+5)^2=4


\implies a(2)^2=4


\implies 4a=4


\implies a=1

Therefore, the equation of the parabola in vertex form is:


y=(x+5)^2