Think about the fact that you can have two types of isosceles triangle: one of them that is a right triangle (isosceles right triangle) such as a 45-45-90 triangle and the other type can be just a regular triangle that has two sides that are congruent but it isn't a right triangle.
Thus, you would need more info about the triangles in order to conclude that the two isosceles triangles are congruent to each other.
It is 1 because if you divided 7over 7 it 1 so x=1
4*(10*12/2)+4*(12*9)+(12*12)= 816 ft^2
the surface area is 816 ft^2.
(1000 mg) / (1.5 (cm cubed)) =
666.666667 kg / m3