System of equations help

1) the total height of an office building (b) and the granite statue that stands on top of it (g) is 326.6 feet. The difference in heights between the building and the statue is 295.4 feet. How tall id the building? How tall is the statue?

2) mountain bike racing currently has 66 teams. The number of non us teams is 30 more than the number of u.s. teams.
Let x represent the number of non u.s. teams and y represent the number of u.s. teams. Write a system of equations the represents the number of u.s. teams and non u.s. teams.
Use elimination to find the solution of the system of equations.
Interpret the solution in the context of the situation.


3) 3c=4d+2
c=d-1
What is c and d?

Problem 1:
b + g = 326.6
b - g = 295.4

from the first eq'n: g = 326.6 - b. Substitute that in the second eq'n for g:
b - (326.6 - b) = 295.4
b - 326.6 + b = 295.4
2b = 295.4 + 326.6 = 622.0
b = 311.0 feet

substitute that back into one of the eq'ns
b - g = 295.4
311 - g = 295.4
g = 311.0 - 295.4
g = 15.6 feet.

Problem 2:
x = 30 + y where x = number of non-US teams and y = number of US teams.
x + y = 66 (given total number of teams)
substitute x = 30 - y in the second eq'n for x:
30 + y + y = 66
2y = 66 - 30 = 36
y = 18 US teams
substitute back into one of the eq'ns:
x + y = 66
x + 18 = 66
x = 66 - 18 = 48 non-US teams

Problem 3:
3c = 4d + 2
c = d - 1 (substitute c in the first eq'n for c:
3(d - 1) = 4d + 2
3d - 3 = 4d + 2
4d - 3d = -3 - 2
d = -5 substitute this value back in one of the eq'ns:
c = d - 1
c = -5 - 1 = -6

Okay first one let x represent building let y represent statue
326.6=x+y
295.4=x-y

okay so use elimination then is an addtion to eliminate y so 622=2x then x= 311 then plug back in and solve for y=15.6