Answer:
b = 12
Step-by-step explanation:
The mistake Megan has made is that she has squared the lengths and then added it instead of taking away the squared length's. The method she used was to work out the hypotenuse, so the correct method would be as follows:
a² + b² = c²
→ Substitute in the values
5² + b² = 13²
→ Simplify the equation
25 + b² = 169
→ Minus 25 from both sides to isolate b²
b² = 144
→ Square root both sides to find the value of b
b = 12
