Answer: 
Step-by-step explanation:
In order to solve this exercise it is important to remember the multiplication of signs. Notice that:

In this case you have the following expression given in the exercise:

Where the variable is "j".
When you multiply signs, you get:

Now you need to identify that like terms and then you need to add them (or combine them). So, applying this procedure you get that the simplified form of the expression is the shown below:

As you can observe, you get a 2nd degree binomial.
Answer:
multiples of 2 2,4,6,8,10,12,14,16,18,20
multiples of 3 3,6,9,12,15,,18,21,24,27,30
Step-by-step explanation:
Lcm is 6
Answer:
6:15
Step-by-step explanation:
because if you multiply 3 by 2 and 5 you will get 6:15 you can also divide 6 and 15 by 3
Hope this is helpful and correct
The answer is 24 since it is the least common multiple
2x + 3y = 12 (1st)
5x − y = 13 (2nd) ---> y = 5x - 13
Substitute y = 5x - 13 into (1st) equation
2x + 3(5x - 13) = 12
2x + 15x - 39 = 12
17x - 39 = 12
17x = 51
x = 3
substitute x = 7 into y = 5x - 13
y = 5x - 13
y = 5(3) - 13
y = 15 - 13
y = 2
Answer
solution x = 3 and y = 2