9.01 prove that the two circles are similar

see the procedure

Step-by-step explanation:

we know that

Figures can be proven similar if one, or more, similarity transformations (reflections, translations, rotations, dilations) can be found that map one figure onto another.  

In this problem to prove circle C and circle A are similar, a translation and a scale factor (from a dilation) will be found to map one circle onto another.

we have that

Circle C is centered at (0,-1) and has a radius of 2 units

Circle A is centered at (3,4) and has a radius of 5 units

step 1

Move the center of the circle C onto the center of the circle A

the transformation has the following rule

(x,y)> (x+3,y+5)

so

(0,-1)> (0+3,-1+5)> (3,4)

center circle C is now equal to center circle A  

The circles are now concentric (they have the same center)

step 2

A dilation is needed to increase the size of circle C to coincide with circle A

scale factor=radius circle A/radius circle C> 5/2=2.5

radius circle C will be=2*scale factor> 2*2.5=5 units

radius circle C is now equal to radius circle A  

therefore

A translation, followed by a dilation will map one circle onto the other, thus proving that the circles are similar

answer:   rlly

step-by-step explanation:

341

step-by-step explanation:

all you have to do is 9x31 (which equals 279) and then 20x31 (which equals 620). then you have to subtract. 620-279=341.