Pythagorean Theorem

Right Triangle: 3-sided polygon containing 1 right angle.

Right Angle: 90˚

Pythagorean Theorem: IN ALL RIGHT TRIANGLES... a² + b² = c²                                         

a² + b² = c²
3² + 4² = x²
9 + 16 = x²
25 = x²
x = 5

How does this work?  Here's one way...

Since side a was 3, it squared is 9.  b is 4, it squared is 16...you can see I put that with the unit pictures... if you rearrange the units of a and b and put them together, you get the picture for c.

Three numbers, such as 3, 4, and 5, are called Pythagorean triples because they can be integer sides of a right triangle.

Directions: Find the integer value for x.

Now we know a² + b² = c², so to find b, we can rearrange it.

b² = c² - a²
x^{2 =} 289 - 225
x² = 64
x = 8

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