What is slope-intercept form?
y=mx+b
How many possible solutions can a system of linear equations have?
one, none/zero, or infinitely many solutions (the line itself)
If you were to use substitution method and your friend uses graphing method on the same system of equations would both get the same solution?
Yes.
Every equation graphs a specific line so no matter how you solve, you get the same solution!
Solve the system:
2x+y=9
-2x-y=-9
These are the same line, so all points on the line are solutions
or
{ (x,y) | 2x+y=9 }
True or False:
It does not matter which method you use when solving systems of linear equations because they will all give you the same answer.
True
How many solutions will a set of parallel lines have?
Zero
What is the first step when solving a system of linear equations using the SUBSTITUTION method?
Isolate one of the variables in one of the equations
then
substitute into the other equation
Solve the system:
y=2x+4
y=2x+5
No solution because they are parallel lines (same slope)
What does it mean to "find the solution" to a system of linear equations?
It means to find the point (x, y) where the 2 lines intersect.
How many solutions will the system in the graph have?
1 solution
Solve the system:
y=2x
3x+y=20
3x+(2x)=20 or
5x=20
x=4
y=8
(4,8)
Solve the system:
y+3x=7
y=-3x+7
They are the same line, so all points on the line are solutions
or
{ (x,y) | y = -3x+7}
At least how many linear equations will be in a system of linear equations?
At least 2 linear equations
What is the solution to the system of linear equations?
(2,2)
How would you isolate x in this equation?
6y+x=20
Subtract 6y from both sides to get:
x=20-6y
Solve the system:
9x+3y=7
9x+3y=5
No solution, they are parallel lines.
How do we write solutions to systems of linear equations?
(x, y)
What is the solution to the system of linear equations?
{ (x,y) | y=2x+1}
or all points on the line
Use the substitution method to solve the system of linear equations:
x=3y
x+y=20
(3y) + y = 20
4y=20
y=5
x=15
(15,5)
Solve the system:
y-2x=4
y-4=2x
They are the same line so there are infinitely many solutions, all the points on the line
or
{ (x,y) | y = 2x+4 }