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:
![\left\{\begin{array}{l}x+y=21\\4x+2y=54.\end{array}\right.](https://tex.z-dn.net/?f=%5Cleft%5C%7B%5Cbegin%7Barray%7D%7Bl%7Dx%2By%3D21%5C%5C4x%2B2y%3D54.%5Cend%7Barray%7D%5Cright.)
From the first equation
Substitute it into the second equation:
![4(21-y)+2y=54,\\ \\84-4y+2y=54,\\ \\-2y=54-84,\\ \\-2y=-30,\\ \\2y=30,\\ \\y=15.](https://tex.z-dn.net/?f=4%2821-y%29%2B2y%3D54%2C%5C%5C%20%5C%5C84-4y%2B2y%3D54%2C%5C%5C%20%5C%5C-2y%3D54-84%2C%5C%5C%20%5C%5C-2y%3D-30%2C%5C%5C%20%5C%5C2y%3D30%2C%5C%5C%20%5C%5Cy%3D15.)
Then
![x=21-15=6.](https://tex.z-dn.net/?f=x%3D21-15%3D6.)
Answer: 6 scateboards and 15 bicycles.
The two given angles are vertical angles and equal each other:
3x + 50 = 6x -10
Now solve for x:
Subtract 3x from both sides:
50 = 3x -10
Add 10 to both sides:
60 = 3x
Divide both sides by 3
X = 20
The answer is the first option, <-20, -42>.
We can find this by first finding what -2u would equal by multiplying <5, 6> by -2. This gives us <-10, -12>.
Then we need to find out what 5v is equal to, by multiplying <-2, -6> by 5 to get <-10, -30>.
Now that we know what -2u and 5v are, we can substitute them into the equation and get
<-10, -12> + <-10, -30>, which we can split up into -10 - 10 = -20, and -12 - 30 = -42, so your final answer is <-20, -42>.
I hope this helps!
What is NOT true about the solution is that it can have different values
This is division!!
Our answer is ninety six (96)
Have a wonderful weekend
Brooke