Help please?

Question

1- the height of a triangle is 18 inches. find the length of the base if the area of the triangle is 63?
2-Find the circumference and area of a circle with diameter 6 inches. use 3.14 for n.
3-If two angles of a triangle measure 40 degrees and 70 degrees, what is the measure of the third.
4-Find the perimeter and area of a square with 12ft side.
5-Find the area of a triangle with base 13ft and height 6 ft.

Answer 1

63 = bh/2
63= b*18/2
b= 63/9 = 7

C= 3.14*6 inches
A = 3.14*6^2/4

180 - 40-70 =70

P = 4*12 = 48
A 12^2 = 144

A= 13*6/2 = 39

Answer 2

1. Area of triangle is A=1/2 bh, so b= 2A/h
b = 2(63)/(18) = 7

2. Circumference of circle is C=2r*pi, Area is A=pi*r*r, r=d/2
C= 2(3)(3.14) = 18.84 in
A= (3.14)(3)(3) = 28.26 sq in

3. Angles have 180 degrees
180-40-70 = 70 degrees

4. P=4s = 2(12) = 24 ft
A= s*s = 12*12 = 144 sq ft

5. A= 1/2 bh
A= (1/2)(13)(6) = 39 sq ft