Answer:
2/7
Step-by-step explanation:
There are 22 (12 + 10) total students in the class. That means that the chance of the first student picked being a girl is 12/22.
Now, we must calculate the chance of the next student to be picked <em>also </em>being a girl - however, there is a trap here! Remember that since a girl has been picked, the total student pool has decreased to 21 and and the total number of girls has decreased to 11. This means the new chance of girl being picked is 11/21.
To find the probability of both these events happening in conjunction, these fractions must be multiplied. 12/22 * 11/21 = 132/462, which simplifies to 2/7.
When you add the equations in (a) you get 7x+y=24.
When you subtract the equations in (b) you also get 7x+y=24.
That means to solve both systems you can work with the same equation. However that is not enough. We must have two equivalent equations. We found only one.
Notice however that in the (b) we can take the first equation and divide every term by 2. When we do this we get 4x-5y=13. That’s the first equation in (a).
So both systems can be solved by working with the same two equations. These are 5x-5y=13 and 7x+y=24. And since we have two equations and two unknowns (the number of equations matches the number of variables) there is only one solution — one x and y that would make both systems true — solve both systems.
Basically we showed the systems are equivalent!
Answer:
10r + 12
Step-by-step explanation:
Answer:

Step-by-step explanation:

Hope this helps!
Answer:
The line would be straight; it could be vertical or horizontal.