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6-8 Accelerated 7 Unit 2 Lesson 14

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K-5 Math •6-8 Math 9-12 Math

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Accelerated 6 •Accelerated 7

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Lesson 1 Lesson 2 Lesson 3 Lesson 4 Lesson 5 Lesson 6 Lesson 7 Lesson 8 Lesson 9 Lesson 10 Lesson 11 Lesson 12 Lesson 13 •Lesson 14 Lesson 15 Lesson 16 Lesson 17 Lesson 18 Lesson 19

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IM K-5 Math
IM 6-8 Math
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Unit 2, Lesson 14

Side Length Quotients in Similar Triangles

Accelerated 7

Practice

Problem 1

These 2 triangles are similar. What are \(a\) and \(b\)?

Note: the 2 figures are not drawn to scale.

<p>Two triangles. First with sides 10, 15, b. Sides with length 10 and 15 form an obtuse angle. Second with sides 4, a, 9. Sides with length 4 and a, form an obtuse angle.</p><br>

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Problem 2

Lesson 14 Resources

Student Materials

Here is triangle \(ABC\). Triangle \(XYZ\) is similar to \(ABC\) with scale factor \(\frac 1 4\).

<p>Triangle A, B C. Side A, B length 4, side B C length 7, side C A, length 5.</p><br>

Draw what triangle \(XYZ\) might look like.
How do the angle measures of triangle \(XYZ\) compare to triangle \(ABC\)? Explain how you know.
What are the side lengths of triangle \(XYZ\)?
For triangle \(XYZ\), calculate (long side) \(\div\) (medium side), and compare to triangle \(ABC\).

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Problem 3

The 2 triangles shown are similar. Find the value of \(\frac d c\).

Two right triangles with each hypotenuse on the same line. First has horizontal side length 7 point 5, vertical side length 9. Second has horizontal side length d and vertical side length c.<br>

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Problem 4

ForLesson 11: More Dilations

The diagram shows 2 nested triangles that share a vertex. Find a center and a scale factor for a dilation that would move the larger triangle to the smaller triangle.

<p>Coordinate plane, x, negative 9 to 3, y, negative 2 to 7.</p><br>

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