Solve each system of equations
12) -2x + 6y = 30
5x + 2y = 10
i really need .

(0,5)

Step-by-step explanation:

-2x+6y=30

5x+2y=10

I'm going to use elimination.

I'm choosing this method because both equations are in the same form.

They are in the form ax+by=c.  

So in order to use elimination, I need one of my columns that contain the variables to contain opposites. Neither one of my columns with the variables have that.  Example -2x and 5x are not opposites and 6y and 2y are not opposite.

I'm going to multiply both sides of equation 2 by -3.  This will help me to achieve the opposites in a column.

So the system becomes:

-2x+6y=30

-15x-6y=-30

If we add the columns you will see that the variable y get's eliminated. Let's do that.

-2x+6y=30

-15x-6y=-30

Adding!

-17x+0y=0

-17x     =0

    x      =0

So using one of the equations (you choose; doesn't matter which one you pick) along with x=0, I'm going to find y.

I choose equation 2.

That is I choose 5x+2y=10 along with x=0 to find y.

5x  +2y=10 with x=0

5(0)+2y=10

0   +2y =10

       2y=10

         y=10/2

         y=5

The solution is (x,y)=(0,5).

to find the total number of combinations, multiply the quantity of each item by each other:

2 pairs of shoes x 3 pairs of shorts = 6 different combinations.