What is the equation of a line?
y=ax+b
How do you find the x-intercept?
Replace y by 0
What's the relationship between parallel lines?
Same slope!
How do you get the slope of a perpendicular line?
Flip-switch the slope
How do you find b?
Replace x,y by a point on the line
What method do you use to find the point of intersection of two lines?
Comparison
2x+4y=8
3x-y=5
Which method would you use to solve this?
Elimination
What is the relative position of the following lines:
y=2x+1
y=-2x+1
Intersecting, but not perpendicular
What is the relative position of the following two lines?
y=1x+7
y=-1x-2
Perpendicular
What is the slope of the following line?
y=2x+1
a=2
What is the y-intercept of the following line?
y=-17x+6
(0,6)
What is the x-intercept of the following line?
y=-2x+6
(3,0)
What would you multiply the first equation by in order to eliminate x?
2x+4y=18
-8x+17y=7
4
By what number would you multiply the second equation in order to eliminate y?
5x+20y=22
7x+4y=13
-5
What is the slope of a line perpendicular to:
y=-7x+1
1/7
The slope of a line is 6. Its y-intercept is -3.
What is the equation of the line?
y=6x-3
The equation of a line is y=-2x+4. What is the equation of a line that is parallel and coincident to it?
y=-2x+4
Find the x intercept of:
y=17x+1105
(-65, 0)
Mario has three times more apples than oranges. If x is the number of apples, and y is the number of oranges, what equation would describe the situation?
x=3y
You sell muffins for 2$ each, and cupcakes for 3$ each. You make 314$ in total. If x is the number of muffins sold, and y is the number of cupcakes sold, which equation translates this system?
2x+3y=314
Find the point that divides line AB in a ratio of 1:5, if:
A(7, 13)
B(19, -5)
(9, 10)
Find the distance between A and B:
A(-2,1)
B(3,-11)
13 units.
When do the following lines intersect?
y=7x+1
y=2x+16
(3, 22)
Find the solution to the following system:
-3x+10y=2
x-5y=1
(-4, -1)
A line has an x-intercept of -5 and a y-intercept of -25. Find its equation.
y=-5x-25