Question

Which sequences of transformations applied to shape I prove that shape I is similar to shape II?

Answer 1

Answer:

Option A and C

Step-by-step explanation:

We are given two shapes I and II.

A point in shape I is at (2,1).

The corresponding point in shape II is at (-1,-0.5).

We know that

The transformation rule when a point is reflected across x- axis is given by

$(x,y)\rightarrow (x,-y)$

By applying this rule on shape then we get

$(2,1)\rightarrow (2,-1)$

The transformation rule when a point is reflected across y- axis is given by

$(x,y)\rightarrow (-x,y)$

Apply this rule then we get

$(2,-1)\rightarrow (-2,-1)$

The transformation when a point is dilate by scale factor 0.5 is given by

$(x,y)\rightarrow (0.5x,0.5y)$

Now, apply dilation by scale factor 0.5

$(-2,-1)\rightarrow 0.5(-2,-1)=(-1,-0.5)$

Therefore, shape I transformed into shape I.

The transformation rule when a point is rotated 180 degree about origin is given by

$(x,y)\rightarrow (-x,-y)$

By apply this rule on shape I

Then , the coordinates of corresponding point after applying the rule

$(2,1)\rightarrow (-2,-1)$

Now, dilation applied on this point and the point is dilated by scale factor 0.5

Then , the coordinated of this point

$(-2,-1)\rightarrow (-1,-0.5)$

Therefore,  shape I transformed into shape II.

Hence,option A and C is true.

Answer 2

Answer:

The sequence of transformations applied to shape I is:

a. reflection across the x-axis, followed by a reflection across the y-axis, and then a dilation by a scale factor of 0.5

Step-by-step explanation:

• Let us consider a point a (2,1) in shape I .

Now when this point is reflected across x-axis the point is transformed to:

(2,-1)

( Since the rule of transformation is:

(x,y) → (x,-y) )

Now again when this point is reflected across the y-axis the point is transformed to:

(-2,-1)

( Since the rule of transformation is:

(x,y) → (-x,y) )

Now when this point is dilated by a scale factor of 0.5 the point that is obtained is:

(-1,-0.5)

( Since, the rule of transformation is:

(x,y) → (0.5x,0.5y) )

Hence, A (2,1) → A' (-1,-0.5)

• Similarly we will consider one more point on the shape I i.e. B(3,1)

Now when this point is reflected across x-axis the point is transformed to:

(3,-1)

( Since the rule of transformation is:

(x,y) → (x,-y) )

Now again when this point is reflected across the y-axis the point is transformed to:

(-3,-1)

( Since the rule of transformation is:

(x,y) → (-x,y) )

Now when this point is dilated by a scale factor of 0.5 the point that is obtained is:

(-1.5,-0.5)

( Since, the rule of transformation is:

(x,y) → (0.5x,0.5y) )

Hence, B (3,1) → B' (-1.5,-0.5)

Similarly all the other points of shape I could be mapped to obtain the shape II.

Hence, option: a is correct.