Question 34954
A triangle that has two 45 degree angles will have third angle as 90 degrees (180-45-45). 
Two sides are the same - Isosceles traingle
Just the angles of a triangle do not specify a specific traingle; thus the area will vary based on length of the sides.
Think about two separate bases; one 5 ft long and the other 10 ft long;
You can draw two 45 degree angles on both of them; The length of the sides will be bigger for 10 ft base than it would be for 5 ft base.  For this reason, a longer base will produce a larger area than the one with a smaller base.