Question

How do I do these 4 geometry please help

Answer 1

Answer:

7) Similar; 8) not similar; 9) ⅔; 10) ⅘

Step-by-step explanation:

Two polygons are similar if

• their corresponding angles are congruent and
• the ratios of their corresponding sides are equal

7) Trapezoids

Corresponding angles are congruent.

$\dfrac{30}{12} = \dfrac{15.5}{6.2} = \dfrac{40 }{16}} = \dfrac{5}{2}$

Corresponding sides are in the same ratio, so the trapezoids are similar.

8) Rectangles

Corresponding angles are congruent.

$\text{Ratio of bases} =\dfrac{42}{35} = \dfrac{7}{5}\\\\\text{Ratio of sides} =\dfrac{24}{25}$

The ratios are different, so the rectangles are not similar.

In similar polygons, the ratio of the lengths of their corresponding sides (the scale factor) is the same.

9. Quadrilaterals

$\text{Scale factor} = \dfrac{10}{15} = \mathbf{\dfrac{2}{3}}$

10. Trapezoids

$\text{Scale factor} = \dfrac{16}{20} = \mathbf{\dfrac{4}{5}}$