You can reduce the first one by combining the ab and the ba term
Answer:
Step-by-step explanation:
SA = bottom rectangle area+side rectangle area + slant rectangle area + 2 triangles
= 26(36) + 10(36)+36(28) +2(0.5)(10)(26) = 2564 cm2
Answer:

Step-by-step explanation:
The surface area of a square pyramid is the sum of the area of the squared base + 4 times the area of each triangular face, therefore:

where:
is the area of the base, where
L is the length of the base
is the area of each triangular face, where
h is the height of the face
Substituting,

For the model in this problem,
L = 12
h = 8
Therefore, the surface area here is:

Answer:
x = 3
Step-by-step explanation:
4 + 12.5 > 11x - 3.5 - 2x
16.5 = 5.5x
16.5/5.5 = x
1 triangle: 2*6 + 1*5
2 triangles: 2*6 + 2*5
3 triangles: 2*6 + 3*5
So for n triangles: p = 2*6 + n*5 = 12 + 5n