Respuesta :

Answer:

x = 5

Step-by-step explanation:

Remember the rule: 5, 12, 13

To prove this rule: Use the equation a² + b² = c²; where as a & b = shorter side, and c is the hypotenuse (longest).

Solve. Let a = x, b = 12, c = 13

a² + b² = c²

(x)² + (12)² = (13)²

Simplify

x² + 144 = 169

Isolate the x. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.

x² + 144 (-144) = 169 (-144)

x² = 169 - 144

x² = 25

Isolate the x. Root both sides

x² = 25

√(x²) = √(25)

x = √25 = √(5 * 5) = 5

5 is your answer for x

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