A. Let x = cheese and
y = chocolate
2x + y = 25
x + y = 20
B. Subtract the second equation from the first.
2x + y = 25
-(x + y = 20)
-—————
x = 5
Plug 5 back in to the second equation and solve for y.
x + y = 20
5 + y = 20
Subtract 5 from both sides.
y = 15
5 cheese and 15 chocolate
Used elimination method because coefficients on the y values were both 1 so it was easy to subtract the equations and eliminate the y variable.
D is under multiplication
You can take it apart. There are a top and bottom (both the same) right triangle. So you can find the area of that by multiplying 8*6 and divide by two. Then multiply by two because there are 2 triangles.
You are left with three rectangular sides: One 10x10, one 10x6, and one 10x8.
So your whole equation looks like this: A = 2[(8*6)/2]+(10*10)+(10*6)+(10*8)
You use the Pythagorean theorem which is a^2+b^2=c^2
So....
.8^2+.6^2=c^2
.64+.36=c^2
1=c^2
1=c becaaue the square root of one is one
