Let the unknown number be x
13x+72= -23x
13x+23x= -72
36x= -72
x= -2
G(X)=6X-3
Y=6X-3
X=6Y-3
X+3=6Y
Y=(X+3)/6
G^-1(9)=(X+3)/6
G^-1(9)=(9+3)/6
G^-1(9)=2
2 4/8 x 3 = 7 4/8
11 3/8 - 7 4/8 = 3 7/8 miles from the end
My brain just says this I not sure if it’s right or not but I think it’s C
Answer: 16
Solution:
1) Use letters to identify the variables:
Number of trumpets: t
Number of clarinets: c
2) Translate each statement into algebraic (mathematical) language.
2.1) Sold a total of 27 used trumpets and clarinets
=> t + c = 27
2.2) Trumpets cost $149 and clarinets cost $99
Total cost of the trumpets: 149t
Total cost of clarinets: 99c
Total cost = 149t + 99c
2.3) Total sales were $3223
=> 149t + 99c = 3223.
3) State the system of equations:
Equation (1) t + c = 27
Equation (2) 149t + 99c = 3223
4) Solve the system of equations:
4.1) Multiply equation 1 by 149:
=> 149t + 149c = 4023
4.2) Subtract the equation (2) from the equation obtained in 4.1
=> 149c - 99c = 4023 - 3223
=> 50c = 800
=> c = 800 / 50 = 16
5) Verify the solution:
From equation (1) t = 27 - 16 = 11
Total cost = 149*11 + 99*16 = 3223
Now you have a verified answer: they sold 16 clarinets
