Algebra I Help Sheet for EOCT

Algebra I Help Sheet for EOCT

SOLVING EQUATIONS

Ø  Look for phrases like:

§  “What is the value of…”

§  “Solve for…”

Ø  Steps to follow:

§  Split the problem into 2 sides using the = sign.

§  Put one side of the equation in Y1=

§  Put the other side of the equation in Y2 =

§  ZOOM FIT (#0)

§  2nd TRACE

§  #5 INTERSECT

§  ENTER 3 times

FINDING AN EQUATION TO MATCH A TABLE

Ø  Look for phrases like:

§  “Which equation describes the data in the table?”

§  “Which function includes all of the data points in the table?”

Ø  Steps to follow:

§  STAT

§  EDIT

§  Be sure you type the x list in L1

§  Be sure you type the y list in L2

§  Go back to STAT

§  Over to CALC

§  If most choices have “plain” x’s ►#4 (LinReg (ax + b))

§  If most choices have x2 ►#5 QuadReg

§  ENTER

Ø  OR YOU CAN DO THE FOLLOWING:

§  Type each answer choice it Y1 =

§  2nd GRAPH to look at the table

§  Then find the table that matches the one you see in the calculator

SOLVING A SYSTEM OF EQUATIONS (2 EQUATIONS TOGETHER)

Ø  Look for phrases like:

§  “What are the coordinates of the intersection?”

Ø  Steps to follow:

§  Make sure Y is by itself!

§  Then, go to Y =

§  ZOOM FIT (#0) ► If you don’t see an intersection ZOOM OUT or IN

§  2nd TRACE

§  #5 INTERSECTION

§  ENTER 3 times

DOMAIN AND RANGE

Ø  Domain is the set of x values

§  On a graph, look for what value the x is at on the left and what value it is at on the right

Ø  Range is the set of y values

§  On a graph, look for what value the y is lowest at and what value the y is highest at

Ø  REMEMBER: an open circle means not included (< or >) and a closed circle means included (≤ or ≥)

GIVEN A GRAPH AND LOOKING FOR EQUATION TO MATCH

Ø  Look for phrases like:

§  “What function is best represented by the graph below?

§  “Which equation matches the graph?”

Ø  Steps to follow:

§  Carefully type each equation in to Y1 =

§  Use either ZOOM STANDARD (#6) or ZOOM FIT (#0) to look at the picture

§  Pay close attention to how the graph crosses the y-axis or the x-axis

§  Use 2nd GRAPH (TABLE) to help as well

GIVEN TWO POINTS AND LOOKING FOR EQUATION TO MATCH

Ø  Look for phrases like:

§  “What equation would pass through these 2 points?”

Ø  Steps to follow:

§  STAT

§  EDIT

§  Type the x-values (the first number in each set of parentheses) in L1

§  Type the y-values (the second number in each set of parentheses) in L2

§  STAT

§  Use blue arrows to go over to CALC

§  #4 LinReg (ax + b)

§  ENTER

X- AND Y-INTERCEPTS

Ø  Remember the x-intercept is where the graph crosses the x-axis

Ø  Remember the y-intercept is where the graph crosses the y-axis

v  EXPONENTS

Ø  Add exponents when they are on the same level

Ø  Multiply exponents when the exponent is being distributed inside of parentheses

Ø  Subtract exponents if the same base is on the top and bottom of a fraction

Ø  REMEMBER: Always use parentheses around a negative number if you are raising it to a power in the calculator.

IF THE PROBLEM INVOLVES ANY GEOMETRY FORMULAS, USE THE FORMULA SHEET!

WHEN IN DOUBT, PLUG THE ANSWER CHOICES IN TO THE FORMULA TO FIND THE CORRECT ANSWER!