Answer:
[tex]\boxed {\boxed {\sf b=60 \ meters}}[/tex]
Step-by-step explanation:
This is a right triangle because of the small square in the corner representing a 90 degree angle.
Therefore, we can use the Pythagorean Theorem.
[tex]a^2+b^2=c^2[/tex]
Where a and b are the legs and c is the hypotenuse.
80 and b are the legs, because they form the right angle. 100 is the hypotenuse because it is opposite the right angle.
[tex]a=80 \\b=b \\c=100[/tex]
[tex](80)^2+b^2=(100)^2[/tex]
Solve the exponents.
[tex]6400+b^2=10000[/tex]
Solve for the unknown by isolating the variable. First, subtract 6400 from both sides.
[tex]6400-6400+b^2=10000-6400\\b^2=3600[/tex]
Take the square root of both sides.
[tex]\sqrt {b^2}= \sqrt {3600}\\b=60 \\b= 60 \ m[/tex]
The missing leg is 60 meters.