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Amiya’s Study Guide…
1. An Rational number is when you can turn a decimal into a fraction or if its already a fraction also a decimal that goes on and on with a PATTERN. An Irrational number is when a decimal that goes on and on WITHOUT A PATTERN. EX. ­5.3, Pi, square root of 16, sqaure rot of 50, .88…., ­⅔ Put these in order. ­⅔, ­5.3, square root of 16, square root of 50, .88….. 2. all the perfect sqaures are… 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 3. .7 written as a fraction is .7/9 and .8 written fraction is 8/9. these are rational because you can put these in a fraction The magic number to turn a decimal to a fraction in this lesson is the number 9. 4. 5. Scientific notation is when you move your decimal to the left or right and it also had an exponent you always times the decimal number by 10 it also can be negative or positive. In order to change standard to scientific notation you have to move the decimal to the left or to the right and once you do that you have to multiply it by 10 to the power the exponent it once you count up your zeros or either how many numbers you have behind the decimal 6. Distributive property is when you have to Multiply once And twice. EX. 2(2x+4) 2*2=4x 2*4=8 so your answer would be 4x+8 don’t ever forget you variable Because if you do your answer would be wrong. 7. Solving equation alway get you variable by itself. In order to get your variable by itself you have to do the two step equation. When you are using distributive property in an equations you alway do the distributive property first because it will make it easier to do. Also when you have variables on both sides you have to make it jump over the bridge(as what we call it) once you make it jump over the bridge the signs change so if you have a negative it changes to a positive. 8. Simplify Equations…. when you are simplify equations like this 5x + 6y ­ 3x + y ­ 2 you have to define you coefficients also constant. In this problem you’re coefficients will be 5, 6, ­3, 1, DON’T EVER FORGET YOU SIGNS. Those will be you coefficients cause a coefficient is the number in front of the variable. In the expression you constant will be ­2. A constant is the number without a variable behind it, Also when you see a variable by itself ALWAY KNOW THAT THERE IS A ONE IT FRONT OF IT. 9. Steepness of a line, Rise over run, change in y over the change in x, vertical change over horizontal change, rate of change. The slope formula is Y2­Y1/X2­X1 10. This is a positive line. A Negative LIne. A undefined Line. A slope of zero. 11. Slope and y­intercept formula= y=mx + b M is the the slope The x is the variable b is the y­intercept. Another name for you slope is rise over run and another word for you y­intercept is your starting amount. To graph y=1/3x + 1 and y= ­5x. first you have to stat with you yintercept you is going to go up the y axis l and the rise one more and run 3. to graph y= ­5x you would just stay on the x axis and go down 5 cause its a negative. 12. Relation= A set of ordered pairs. Function= a relation where every z has on one y and x isnt doing any cheating. Domain= input, x, and independent. Range= Output, y, dependent. Input= domain. Output= Range. Independent= Domain x. Dependent= Range,y. Vertical line test= to see if the graphs are a function and if it hit once its a function hits more than one timeits not a function. 13. linear is a line. Non­linear is not a line. a graph you can tell if its a line or not a line. equation you can tell if it in the slope yintercept formula. A table you can see if it is a constant rate of changes. 14. Reflection, Translation, Dilation, Ralution. 16. Pythagorean Theorem formula is A secong plus B to the second I would type the formula but i dont know how to do the number to the second power. 17. A system of equation is where two or more equation combine. 1 solution, No solution, Infinet solution. example one soultion could be y=2x + 6 and y=3x + 5 it will cross. example two for o solution would be y=5x + 10 and y=5x + 25. example for infinte would be y= 8x + 63 and y=8x + 63. 18. A scattered plot is graphs that is used to show corretations or relationships among data. You used this for two peices of data. Positive scattered plot Negative scattered plot No relationship A trend line is where you balance the dots and you draw the line straight through them. 19. y=5x + 10 would be your function. 20. l* W * H, radius formula is 3.14r2. circumfrence formula is 3.14 * d or 3.17r. Volume formula is l* w* h/3, v= 3.14r2h3, 3.14r3h