Answer:
a = sqrt(7)
Step-by-step explanation:
Since this is a right triangle, we can use the Pythagorean theorem
a^2 + b^2 = c^2
where a and b are the legs and c is the hypotenuse
a^2 +3^2 = 4^2
a^2 +9 = 16
a^2 = 16-9
a^2 = 7
Taking the square root
a = sqrt(7)
