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
Answer: B) A=1/2(7)(12).
Explanation: The formula for area of a triangle is 1/2bh. Only B maintains this formula.
Answer:
20 years old
Step-by-step explanation:
Joe = J
Sydney = S
J = 5 + S
J + S = 45
Substitute
5 + S + S = 45
Add
5 + 2S = 45
Subtract 5 from both sides of the equation
2S = 40
Divide both sides of the equation by 2
S = 20
Sydney is 20 years old
Hope this helps :)
Answer: if we divide the numerator and denominator by two, we get that he can paint two paintings in one hour. His unit rate is 2:1.
4:2 divide by two to make the denominator 1
2:1 solution has 1 in the denominator
Step-by-step explanation:
-5x-10=10 x= -4
Work:
-5x-10=10
+10 +10
______________
-5x=20
_______
-5 -5
x=-4