Answer:
11.3
Step-by-step explanation:
Set up your equation:
a² + b² = c²
Plug in your values:
a² + 4² = 12²
Get a² by itself:
a² = 12² - 4²
Square your numbers and subtract:
a² = 144 - 16
a² = 128
Find the square root of both sides:
√a² = √128
a = 11.3
