 Similar figures have the same shape, but not necessarily the same size. (((add to vocabulary section of your notebook)))

14 m 7m 60° The ratio formed by the sides is the scale factor: 14m = 2m 7m 1m

 For every 5 centimeters in height for me, my mini-me had 1 centimeter.  The scale was figured out by dividing 1 by 5:  0.2 = 20% This means that to find your mini- me’s size, you would either multiply by 0.2 or divide by 5.

A picture 10 in. tall and 14 in. wide is to be scaled to 1.5 in. tall to be displayed on a Web page. How wide should the picture be on the Web page for the two pictures to be similar? To find the scale factor, divide the known measurement of the scaled picture by the corresponding measurement of the original picture = Then multiply the width of the original picture by the scale factor = 2.1 The picture should be 2.1 in. wide.

To find the scale factor, divide the known measurement of the scaled painting by the corresponding measurement of the original painting = Then multiply the width of the original painting by the scale factor = 14 The painting should be 14 in. wide. A painting 40 in. tall and 56 in. wide is to be scaled to 10 in. tall to be displayed on a poster. How wide should the painting be on the poster for the two pictures to be similar?

Set up a proportion.24 ft x in. 18 ft 4 in. = 18 ft x in. = 24 ft 4 in.Find the cross products. A flag in the shape of an isosceles triangle with side lengths 18 ft, 18 ft, and 24 ft is hanging on a pole outside a campground. A camp t-shirt shows a smaller version of the triangle with two sides that are each 4 in. long. What is the length of the third side of the triangle on the t-shirt? 18 ft 24ft 18x = 96 x =  Multiply Solve for x. The third side of the triangle is about 5.3 in. long.

A 8 ft 4 ft B6 ft 3 ft C 5 ft 2 ft Since the three figures are all rectangles, all the angles are right angles. So the corresponding angles are congruent. Compare the ratios of corresponding sides to see if they are equal.

A 8 ft 4 ft B6 ft 3 ft C 5 ft 2 ft The ratios are equal. Rectangle A is similar to rectangle B. The notation A ~ B shows similarity. 24 = 24 length of rectangle A length of rectangle B width of rectangle A width of rectangle B ? =

A 8 ft 4 ft B6 ft 3 ft C 5 ft 2 ft The ratios are NOT equal. Rectangle A is NOT similar to rectangle C. 16  20 length of rectangle A length of rectangle C width of rectangle A width of rectangle C ? =