identical variables with same exponents on each variable
Subtract: 8x-3x
=5x
Add: 4x+ 3x
= 7x
Polynomial
To subtract, add its opposite: (3y+5)-(7y-4)
=(3y+5)+(-7y+4)
=3y+5-7y+4
=3y-7y+5+4
=-4y+9
To add, remove bracket, collect like terms: (2p-2)+(4p-7)
= 2p-2+4p-7
= 2p+4p-2-7
= 6p-9
Made up of term(s) connected by addition or subtraction
operators.
Expression VS Equation
Has an equal sign
Fractions can be removed (by finding LCD)
We can solve
Does not have an equal sign
Can't remove fraction (only expand)
We can only simplify
Modelling with Algebra
Example: Alexa works at a record shop. She earns $!0.70/hr plus $0.88 for each album she sells. To model this situation we can say, "h " is the number of hours worked and "a" is the number of albums sold. The expression would be 10.70 h + 0.88 a
It is a representation of a pattern of numbers.
Modelling with Formulas
To rearrange, isolate the term that contains the variable, and then isolate the variable.
Algebraic relationship between two or more variables.
Equations with fractions
For more than one fraction, find the LCD and multiply all the terms on both sides of equation by this value.
To solve an equation with Multiple Terms, collect variable terms one side and constant* terms on the other by doing opposite operation. Ex: 3x +2 = 2x -4
3x +2 -2x = 2x -4 -2x
x +2 = -4
x +2 -2 = -4 -2
x = -6
Simple Equations
You can also do a check: L.S. = 2(8) - 7 R.S. = 9
=16 - 7
= 9
L.S. = R.S.
To solve a 2 step equation, either add or subtract to isolate the variable term. Then divide by the coefficient of the variable term. Ex: 2x -7 = 9
2x -7 +7 = 9 +7
2x = 16
2x/2 = 16/2
x=8
Keep in mind that you are using SAMDEB
To solve one step equation, do opposite operation to isolate the variable. Ex: x+4=13
x +4 -4 = 13 -4
x=9
Equation is a statement that say 2 expressions are equal. Ex: 3x+3=2x-1
Solution or root of an equation is the value of the variable that makes an equation true.