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Solve the systems of linear equations by graphing. State whether the system is consistent/inconsistent, dependent/independent.x + y = 63x - 4y = 4

User Parthasarathy
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We have the next system of equations

x + y = 6

3x - 4y = 4

First, we will isolate the x of the first equation

x=6-y

then we will substitute the equation above in the second equation

3(6-y)-4y=4

Then we simplify

18-3y-4y=4

we sum like terms

-7y=-18+4

-7y=-14

y=-14/-7

y=2

then for x

x=6-2

x=4

Because we obtain one solution we can say that the system is independent and consistent

If we want to solve by graphing we need to graph each equation by calculating some points

For the first equation

x+y=6

we isolate the y

y=-x+6

x=0

y=6

Point (0,6)

x=-3

y=-(-3)+6

y=9

Point (-3,9)

For the second equation

3x-4y=4

we isolate the y

y=3/4x-1

x=0

y=-1

Point (0-1)

x=-4

y=3/4(4)-1

y=-3-1=-4

Point (4,2)

Then we graph the lines by connecting the points we calculate

The line in blue is x+y=6

The line in green is 3x-4y=4

The point where the two lines intercept each other is the solution in this case (4,2) as we can verify previously

Because the lines intercept in only one point we can say that the system of equations is consistent and independent

Solve the systems of linear equations by graphing. State whether the system is consistent-example-1
User Dynite
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