Answer:
b=3
Step-by-step explanation:
Pythagorean theorem
a²+b²=c²
use simple algebra to get the equation to say
a²-c²=-b² by subtracting b² on both sides and c² on both sides
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plug in you numbers
4²-5²=b²
do the math
16-25=-9
square root it
b=√-9
b=3
