What is the value a2 +3b divided when =3,b=8,c=2,and d=5?

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much

Which of the following three dimensional figures has a circle as it’s base

The point of intersection of the diagonals of a rectangle is 4 cm further away from the smaller side then from the larger side of the rectangle. the perimeter of the rectangle is equal to 56 cm. find the lengths of the sides of the rectangle. 16 points answer quick