Florida B.E.S.T. MA.8.GR.1

MA.8.GR.1 is a B.E.S.T. standard. These are the benchmarks under it.

• MA.8.GR.1.1

  Apply the Pythagorean Theorem to solve mathematical and real-world problems involving unknown side lengths in right triangles.

• MA.8.GR.1.2

  Apply the Pythagorean Theorem to solve mathematical and real-world problems involving the distance between two points in a coordinate plane.

• MA.8.GR.1.3

  Use the Triangle Inequality Theorem to determine if a triangle can be formed from a given set of sides. Use the converse of the Pythagorean Theorem to determine...

• MA.8.GR.1.4

  Solve mathematical problems involving the relationships between supplementary, complementary, vertical or adjacent angles.

• MA.8.GR.1.5

  Solve problems involving the relationships of interior and exterior angles of a triangle.

• MA.8.GR.1.6

  Develop and use formulas for the sums of the interior angles of regular polygons by decomposing them into triangles.

01

What Students Need to Do

Students identify the hypotenuse and calculate missing side lengths in right triangles. They use side lengths to test whether a triangle is right. They find missing interior and exterior angles using known triangle relationships.

02

What Mastery Looks Like

Given a right triangle in any orientation, a student identifies the hypotenuse, writes the correct equation, and solves accurately. The student can use side lengths to classify a triangle as right or not right. They find missing interior and exterior angles and explain the relationship used.

03

Common Misconceptions

Students often label the unknown side as c even when it is not the hypotenuse. They may add side lengths instead of their squares, or forget to take a square root. With angles, they may confuse an exterior angle with its adjacent interior angle or use the wrong remote interior angles.

04

How to Assess It

Give a two-part exit ticket: find the missing leg when the hypotenuse is 13 and another leg is 5, then find an exterior angle with remote interior angles of 48° and 67°.

1. 01

   Build 3-4-5, 5-12-13, and non-right triangles with craft sticks, then measure angles and compare squared side lengths.

2. 02

   Write a response to: How can side lengths prove a triangle is right, and how can one angle determine another?

3. 03

   Play a card match pairing triangle diagrams with missing-side equations, angle equations, and solutions.

4. 04

   Measure a ladder’s height and ground distance, then calculate its length and check the result with a tape measure.

• MA.912.T.1.2

  Solve mathematical and real-world problems involving right triangles using trigonometric ratios and the Pythagorean Theorem.

• MA.912.GR.1.3

  Prove relationships and theorems about triangles. Solve mathematical and real-world problems involving postulates, relationships and theorems of triangles.