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What is the equation of the graph below?
A graph shows a parabola that opens down and crosses the x axis near one and a half and four and a half.
A) y = − (x + 2)2 + 2
B) y = − (x − 3)2 + 2
C) y = (x − 2)2 + 2
D) y = (x + 3)2 + 2

Respuesta :

Answer:

B) [tex]y=-(x-3)^{2}+2[/tex]

Step-by-step explanation:

We are given,

The graph of the parabola opens downwards.

This means that the leading co-efficient of the function will be negative.

So, options C and D are not possible.

Moreover, it is given that the graph cuts x-axis near [tex]1\frac{1}{2}[/tex] i.e. [tex]\frac{3}{2}[/tex] = 1.5 and [tex]4\frac{1}{2}[/tex] i.e. [tex]\frac{9}{2}[/tex] = 4.5.

i.e. At y=0, the value of x is near [tex]\frac{3}{2}[/tex] and [tex]\frac{9}{2}[/tex].

A. So, in [tex]y=-(x+2)^{2}+2[/tex], we put y =0.

i.e. [tex](x+2)^{2}=2[/tex]

i.e. [tex]x=-2\pm \sqrt{2}[/tex]

i.e. x = 0.68 and x = 3.41

We see that this does not crosses the x-axis at the given points.

So, option A is wrong.

B. Also, in [tex]y=-(x-3)^{2}+2[/tex], we put y =0.

i.e. [tex](x-3)^{2}=2[/tex]

i.e. [tex]x=3\pm \sqrt{2}[/tex]

i.e. x = 1.68 and x = 4.41.

Thus, this equation cuts the x-axis near the given points i.e. 1.5 and 4.5.

Hence, the equation of the given graph is [tex]y=-(x-3)^{2}+2[/tex].