Let x be a number of skateboards and y be the number of bicycles in Eddie's repair shop.
Eddie asks the girls to order 54 new wheels for 21 skateboards and bicycles, then
x+y=21.
One scateboard has 4 wheels, then x scateboards have 4x wheels, one bicycle has 2 wheels, then y bicycles have 2y wheels. In total there should be ordered 54 wheels, so
4x+2y=54.
Solve the system of equations:

From the first equation
Substitute it into the second equation:

Then

Answer: 6 scateboards and 15 bicycles.
Answer:
Step-by-step explanation:
You know the lengths of two sides and the angle between them, so use the Law of Cosines to find the third side.
x^2 = 10.5^2+ 5.4^2 -2(10.5)(5.4)cos20°
x ≈ 5.73 units
3(5)+15= 30
because BIDMAS so we would multiply 3 by 5 then add the answer which would be 15 to 15 and we would get 30.
Answer:
The answer to this is: 132
Step-by-step explanation: