(5.1)
Solve using substitution:
a) 4x+3y=-13
b) y=x+5
(-4,1)
Find the value of the determinant:
-4 -3
7 4
Determinant = 5
(9x+29)/(x^2+7x+12)
Factor denominator first: (x+3)(x+4)
then would be:
(9x+29)/(x+3)(x+4)=A/(x+3)+B/(x+4)
Identify the graphs:
1. x+y=24
2. x^2+y^2=100
1. Line
2. Circle
Find w, x, y & z:
|-7 x|= |w -4|
|y -2| |-2 z|
w= -7
x= -4
y= -2
z= -2
Solve using substitution:
a) 3x+4y=4
b) x-y=13
(8,-5)
Solve using Gaussian Elimination:
3x+6y=9
-4x+y=33
(-7,5)
Without solving, how would we set up this partial fraction decomposition:
(5x+4)/(x+2)^3
(5x+4)/(x+2)^3=A/(x+2)+B(x+2)^2+C/(x+2)^3
Identify the graphs:
1. y=x
2. y-2x=6
3. y=x^2+10
4. x=-y^2
1.Line
2. Line
3. parabola
4. Parabola
Find A + B:
|-3 9|+ | 8 2|
|-5 0| |-4 10|
|5 11|
|-9 10|
Solve using elimination (the addition method):
a) 3x-7y=15
b) 3x+7y=15
(5,0)
Write the system of equations associated with the augmented matrix:
1 1 0 2
0 4 1 -5
1 0 -1 8
x+y=2
4y+z=-5
x-z=8
Identify the graph of each:
1. x+y=5
2. x^2+y^2=9
3. y=2x^2
1. Line
2. Circle
3. Parabola
How should we draw the lines for this graph?
x+y<4
x-2y>6
Both the lines should be dashed
Find 4A:
4 | -3 9|
| -5 0|
|-12 36|
|-20 0|
Solve using elimination:
a) 9x-5y=1
b) -18x+10y=1
No solution
(answer: 0=3)
Use Cramer's Rule to solve:
x+y=6
x-y=2
(4,2)
Solve:
x^2=y-1
y=3x+5
(4,17),(-1,2)
Identify the type of graph and if the line should be dashed or solid:
1. x^2+y^2<4
2. y<_ x (y is greater than or equal to x)
1. Circle and dashed line
2. Line and solid line
Find A*B:
|-3 9|*|8 2|
|-5 0| |-4 10|
|-60 84|
|-40 -10|
What is the ordered pair called that we find.
Mrs. B and the textbook refer to this ordered pair as the solution to the system. But what is this solution?
The solution is called the "Point of Intersection"
Solve the equation for x:
6x x =25
25 x
(-5/6,5)
How many solutions can a circle have?
Circles can have 0, 1, or 2 solutions
What is the shortcut method to find out where to shade the graph at?
The shortcut method:
if y is (+) > shades above and < shades below
if y is (-) > shades below and < shades above
Solve:
|5 6|*|1 0|
|8 9| |0 1|
|5 6|
|8 9|