How do you solve a system of equations by elimination? How do you solve a system of equations by substitution?

IF you have two equations with the 2 variables, x and y, you can substitute one y-value with the other, then solve.

Step-by-step explanation:  For example:

y = 2x + 4

3x+y = 9

We can substitute the value of y from the first equation, 2x + 4, into the second equation.  So, the second equaton becomes:

3x + 2x + 4 = 9

Now solve for x:

5x + 4 = 9

5x = 5

x = 1

This value of x then can be used to find y, by substituting in the value "1" for x in the first equation:

y = 2x + 4 = 2(1) + 4 = 2 + 4 = 6

So, the solution to this linear system is (1, 6)

exa:

)

3+11

14

step-by-step explanation:

from this example, we can see that subtracting with integers is the same as adding the opposite. we can solve using a number line or by using the saying "keep, change, change" to us solve. it is important to remember that we can subtract a negative and end up with a larger number than we started with.