Answer:
sum of the polynomials is 
Step-by-step explanation:
Given polynomial is (7 x^3– 4 x^2) + (2 x^3 +3 x)
adding x^3 terms, now we get


Therefore the sum of given polynomial is

Note that a squared pyramid has a square base & 4 equal triangles.
To find the lateral the lateral area you calculate the area of the 4 equal triangles and to find the surface area (total Area) you add the area of the base:
Area of each triangle = side (5) x slant (9) and you divide by 2
==>Aera of 1 triangle = (9x5)/2 = 45/2 & for the 4 triangles
Lateral area = (45/2) x 4 = 90 in²
Now the base area (square) = 5 x 5= 25 in²
so the surface area = 90+25 = 115 in² (answer a)
Y=3x has a positive slope, and Y=-3x has a negative slope.
So, Angelique took away a a number from the two numbers and did not replace it with the correct number. So, this should be 1-51=50. Hope I helped! :)
I think the answer is c 30 degrees!!