Math 10 concepts
Linear relations
Slope
Measurement of steepness
Formula: m = Rise (vertical)/Run (horizontal)
m = (y2 - y1) / (x2 - x1)
Rise: Up is positive, down is negative
Run: Right is positive, left is negative
Line that goes up to right is positive slope
Line that goes down to left is positive slope
Line that goes up to left is negative slope
Line that goes down to right is negative slope
Horizontal line slope = 0 bc of 0/run
Vertical line slope = undefined bc of rise/0
Slope-intercept form
Formula: y = mx + b
m = slope
b = y-intercept
How to graph
Start with y-intercept
Using slope, find rise and run
If slope is not fraction, run = 1
ex. y = 4x + 5, then 4 = 4/1
Parallel & perpendicular
Parallel: Slope = same, y-intercept = different (Symbol ∥)
Perpendicular: Slope = negative reciprocal
(Symbol ⊥)
Equations of linear functions
Slope-point form
Formula: y - y1 = m (x - x1)
m = slope
(x1, y1) = point on line
To write any equation, need slope and a point on line
General form
Formula: Ax + By + C = 0
Both A and B cannot be zero
A is a whole number (not fraction)
X intercept: y = 0 (x, 0)
Y intercept: x = 0 (0, y)
Horizontal line equation: y = value (x ∈ R, slope = 0)
Vertical line equation: x = value (y ∈ R, slope = undefined)
General form: if A > 0, B > 0, C > 0, then: negative slope
negative y-intercept
negative x-intercept
General form: if A < 0, B > 0, C > 0, then:
positive slope
negative y-intercept
positive x-intercept
Arithmetic sequence
Number pattern increasing or decreasing at a constant rate
Difference between terms = same
2, 4, 8, 16, 32.... (not an arithmetic pattern)
Formula: d = t2 - t1
d = difference
t = term
General term formula
Formula: tn = a + d(n - 1)
tn = term at nth position
a = first term
d = difference
Steps to plot as linear equation in graph
- Equation: tn = dn + a
- Plot y-intercept (a)
- Use slope (d) = rise/run to get next point
- Continue plotting rest of points
- Do NOT join points into line because n is only natural numbers
- Remove y-intercept because n CANNOT be zero
Diff between linear function and arithmetic sequence
- Linear: y-intercept; arithmetic: NO y-intercept
- Linear: continuous, infinite points; arithmetic: no line, distinct points
Linear systems
Study of two or more equations
Ordered pair that satisfies both equations is the solution of the system
Find solution: graph the two lines and the point of intersection is the solution
Parallel lines have NO SOLUTION because they cannot intersect - inconsistent system
Lines have same slope, same y-intercept, then infinite solutions - consistent system
Lines have different slope, then ONLY ONE solution - consistent system
Solving by elimination
If the x or y variables differ in signs, eliminate through ADDITION
If x or y variables are exactly the same, eliminate through SUBTRACTION
If you multiply linear equation by constant, does not change the solution
Solving by substitution
- Using equation with variable that has coefficient of 1, solve that variable
- Substitute that solution in the other equation
Simplifying Polynomials
If given x and y values for polynomial, input where is it appropriate and remember to put brackets around them
Then evaluate exponents first, if any
Exponents
-n^m = always negative
(-n)^m = if m is odd, answer is negative. If m is even, answer is positive.
Multiplying powers /w same base= add exponents
Ex. n^m x n^p = n^(m + p)
Dividing powers /w same base = subtract exponents
Ex. n^m ÷ n^p = n^(m - p)
Law of exponents: n^0 = 1
-n^0 = -1
(-n)^0 = 1
Law of exponents: (n^m)^p = n^m x p
Negative exponents: n^-m = 1/(n^m)
Negative exponent in the numerator: bring to denominator to make it positive
Negative exponent in the denominator: bring to numerator to make it positive
Relations and functions
Relation
Ordered pair
Domain: first set of elements (Surrey, BC), x value(s)
Range: second set of elements (Surrey, BC), y value(s)
*Do not repeat listing of same number in domain or range
Linear relation
A relation with ordered pairs graphed in a straight line
Values of x and y increase/decrease by a constant amount
- Degree of equation = 1 (NO x^2 + y^2)
- Variables cannot multiply (NO xy)
- Variables cannot be in denominator (NO y = 7/x+3)
- Variables cannot be exponent (NO y = 7^x)
Function
Each element in domain is associated with EXACTLY one element in range
Tip: in a table, if any X (domain) value repeats, it is NOT a function
Tip: in a graph, any two points on same x axis, is NOT a function
Any points joined by vertical line, is NOT a function
- Arrows = line extends
- Solid dot = end point
- Outlined dot = approaching, but NOT REACHING end point
Inequality symbols
greater than: >
less than: <
greater than or equal to: ≥
less than or equal to: ≤
Tip: Smaller number then variable then larger number
Tip: always read from variable to the number
Set Notation
{} = set
| = such that
∈ = is an element of
R = real number
Interval Notation
] = end number is included
) = end number is NOT included
∞ = NO endpoint
Ex. A range of numbers greater than -2 = (-2,∞)
Ex. y is an element of real numbers such that y is greater than -2 = {y | y > -2, y ∈ R}
There is a simplified option = y > -2
To find y intercept, put x = 0
To find x intercept, put y = 0
Graph the equation using x and y intercepts
Input values are independent variables (x)
Output values are dependent variables (y)
Discrete data = points NOT connected in graph (integers)
Continuous data = points connected in graph (real numbers)
Rate of change = change in dependent variable ⁄ change in independent variable
Also known as... Slope = rise ⁄ run
F(x) represents function
y = 2x + 1 represented as f(x) = 2x + 1
Distributive law: a(b+c) = ab + ac
If bases are the same, then exponents are the same
Ex.5^(x+4) = 5^(-2), so x+4 = -2
General rule of fractional exponents: numerator is the power and the denominator is the root.
We can write x^(m/n) as n√(xm)
To simplify radical form, multiply numerator and denominator by the root because you cannot have root in denominator
FOIL (First, Outside, Inside, Last) Method
(a + b) (c + d) = ac + ad + bc + bd