True/False?
3<8
True
On a number line, which way do the negative numbers go?
Down if on the y axis and to the left if on the x axis.
What is a system of equations?
2 or more equations with the same variables.
Solve the system by elimination.
x+y=10
x-y=4
(7,3)
Solve by substitution.
y=2x
2x+y=12
(3,6)
Solve
6x+2+6x<14
x<1
An open circle on the number line tells you that the endpoint (number) is _________________.
Not included.
What are the 3 ways to solve systems of equations?
Graphing, substitution, and elimination.
Solve by elimination.
x+y=6
-x+y=-4
(5,1)
Solve by substitution.
x=2y+1
x+3y=16
(7,3)
When do you need to reverse of switch the direction of the inequality symbol?
1. When you multiply or divide by a negative number.
2. When you solve the inequality and the variable comes out on the right side of the inequality. Flip the entire answer.
A closed circle tells you the endpoint or number is __________ and that the number is an answer of the solution set.
Included
When graphing systems of equations, the equations need to be in _______________________ form or ______________.
Slope-intercept form or y=mx+b
Solve by elimination.
2x-3y=9
x+3y=0
(3,-1)
Substitution.
x=2y
4x+y=18
(4,2)
Solve.
2(x-3)>10
2x-6>10
add 6 to both sides
2x>16
divide by 2 on both sides
x>8
When graphing an inequality, what do you graph first?
The y-intercept or the "b".
Graph this system of equations and write the solution down in ordered pair format.
x-y=6
2x+y=3
(3,-3)
Solve by elimination.
3x=5-7y
2y=x-6
(4,-1)
Substitution.
y=3x+2
2x-3y=8
(-2,-4)
True/False
7>3 and 2>10
False
What is the y-intercept and the slope of this inequality?
2x+y>1
y>-2x+1
m=-2 or -2/1
b=1
Solve by graphing and write answer as an ordered pair.
y=-3+2
y=2x-3
(1,-1)
Solve by elimination.
2x+3y=15
x-3y=3
(6,1)
Substitution.
4y+31=3x
y+10=3x
(1,-7)