Can anyone plz help me with pre algebra or give some hints on the best way to understand it?

Question

I'm in 8th grade and i'm learning pre algebra with an online school and i have never really been good at math but have also never failed but this year i suck and i have a feeling its just the algebra??

Answer 1

Hi Mara:



here are my tips:



1) read the problem through; until you understand it.



2) look for clue words like: sum, more than,less than, greater,multiplied,divided by..etc

for all word problems



3) look for given equation, variables, etc



4) find out what the problem is asking you to solve for .



5) write "Given: " , than what is given, than write what your solving for



6) if you have to rearrange the equation in order to solve it, than write out step by step what math

operation your using on it to solve it, if you have to rearrange it otherwise to 7



7) Write step by step what Math operation your using to solve for it . This will make it

easier for you to backtrack it and see what you did wrong; if you made error in your

math - if your proof for it, doesn't check and equal



8) While doing number 6 and 7: Pay Attention To the Signs . This the one number

reason why people make a errors in Math answers when solving there math problem



9) Do a Proof to prove your answer is correct. By writing "Proof:" - The reason for this : Sometimes you might think you have the right answer when your really got the wrong one but this will tell you right away. do the following:



10) write your original equation down ,plug in your numbers, than write step by step

what Math operation your using to solve for it . If this does not check and equal than

back track for your answer in the first part. If they check out than check the Proof and see if you made a error . As soon as you find your error . Correct it, than solve it again and redo the proof again until it check and equals



11) If your not sure of how to do a problem , ask a good friend or a good teacher who is good in math to help you, okay.



12) Sometime ask the web for help, you want to find the surface area of a cone; just type in "Surface area of a cone" in one of the search engine boxes press enter and see what pops up click a few of them and see if you can find the equation



Wikpika - is a good source for math, help so is yahoo, bing is a hit and miss but they can be a big help.



Once you find a new equation - Than write it down along with what is with a few example; in a notebook and you will have it at side ready to aid in your time of confession or doubt, okay. Just be sure to add any other equations you encounter in math and they always be ready to assist you like a flaming sword makes a enemy stop in his track so will this aid you.



13) Make sure you put the units on the end of the final answer. Some teacher will mark it wrong if it not there. Here a example of of a math problem so you get a idea of how to do one :



example:



A spherical tank need to hold 100 cubic feet of water, using the formula V= 4/3*pi*r^3 ,

and pi = 3.14159258, what is the radius of the tank:



step 1



Given :



pi = 3.14159258

V = 4/3 * pi* r^3

V= 100

where are solving for r





Step 2



V = 4/3 * pi* r^3 - original equation



100 = 4/3* 3.14159258 * r^3 - Substitution of V, and pi



100* 3/4 = 4/3* 3.1415258 * r^3 * 3/4 - Multiplying the multiplicative inverse of a

number to both sides of the equation to move it to the other side of it



300/4 = 3.14159258 * r^3 - Multiplication



75 = 3.14159258 * r^3 - Division



75 * 1/3.14159258 = 3.14159258* r^3 * 1/3.14159259 - Multiplying the multiplicative

inverse of a number to both sides of the equation to move it to the other side of it



75/3.14159258 = r^3 - Multiplication



23.873242023000 = r^3 - Division



23.873242023000 ^ (1/3) = (r ^ 3)^(1/3) - taking the cube root of both sides of the

equation to remove the cube



2.879411933968 = r - doing or solving the cube root



The answer for r is 2.879411933968 feet



Proof:



Prove that - When r = 2.879411933968, pi = 3.14159258 and v = 100 cubic feet.

It make the V =4/3 * pi* r^3 true



V = 4/3 * pi* r^3 - original equation



100 = 4/3 * 3.14159258* 2.879411933968^3 - substitution of r,V,pi



100 = 4.1887904* 2.879411933968^3 - Multiplication and Division of 4/3 and pi



100 = 4.1887904 * 23.87324202301 - solving or taking the cube of r



100 = 100 - Multiplication



It checks and equals



The answer for r is 2.879411933968 feet



Granted doing this, takes a lot of time; but it will give you the right answers every time; or at least catch your wrong answers before you write it down

and it will save your bacon every time , A lot of right answers is better than a lot of wrong answers don't you think.



Also type "Free Math Help Websites" in the yahoo search box and pick a few. To find out which websites can best help you with math. Okay



I hope this helps

Answer 2

algebra, which will become integral in any higher maths you study, is about using symbols (usually letters) to represent unknown values, and provide a way of working out those values or giving relations between them. I see you are in year 8 and I will try to explain it as well as I can because I remember when I was first confronted with algebra lol.

So in something simple like 5x = 15 we know that x represents a particular value and that this value is one fifth of 15. To work it out we divide both sides by 5 (always do the same to both sides to keep it equal) and we get x = 3. And of course we know that 5 x 3 = 15, so that answer is correct.

In more complex things, we can't always find what the unknown values are but we can still formulate relationships based on the values that we do know and by using symbols for those values that we don't know. For example, the polynomial ax2 + bx + c may represent a function (let's just say it the graph of y = ax^2 + bx + c. Now, y and x and represent the vertical and horizontal points on a graph and the above polynomial relation gives the relationship between y and x for any particular point on the graph.

If we were to graph y = 5x then the relationship between y and x is that for any x-value (the horizontal direction) the y-value (vertical) is 5 times that. So at the point where x equals 4, then the y value is 20. Also this is a linear graph. We can say that the gradient (slope) is 5. In other words, every time you move right one point, you must move up 5 (or down 5 if you move left). The graph of this will look like a diagonal line. This is called a linear graph because it is a straight line. Anything graph where y = (something)x is a linear graph and the (something) is the gradient.

Now, y = ax^2 + bx + c is more complex. It is not a straight line, but instead it is a curve, sort of like a hill. Without numbers we don't know exactly what it looks like, but any ax^2 graph will have a that sort of shape while the bx will change it's width and c represents the y-intercept i.e. where the graph crosses the y-axis. This is the most simple part of a graph to work out because the y-axis will be crossed when the x-value is 0. Let's use this in the function I had before.

y = 5x + c. I've added a c to this function. Now the only difference from before is that the straight line graph will be moved vertically upward or downward. Given a point on the graph, say (5,6) i.e. x=5, y=6 then we can work out c. Substituting these values we get 6 = 5(6) = c which is 6 = 30 + c so we subtract 30 from either side to get c, -24 = c. So the relationship is y = 5x -24. This means the graph has a gradient of five and will pass the point (0, -24). From this, the full graph can be drawn because we can work out any y-value.

Now, i won't say anymore because I've already said lot and I'm not sure how much you already knew. I've left y = ax^2 + bx + c alone, because it's too complex i think for someone just starting but maybe you can see how they form a particular relationship. And every algebraic equation has a graph and understanding that should help once you get your head around it.

Hopefully that has helped but I don't know how much you already knew or didn't know. So please email me if you want.

Answer 3

My granddaughter is doing pre-algebra. Sometimes she watches the Khan Academy videos on YouTube. They give pretty clear explanations.



It's really all about accepting the idea of letters standing in for numbers.



Then the other concept that runs through everything is that you can do anything to an equation as long as you do the same thing to both sides.



So x+y= 6 is the same as



2x + 2y = 12 (everything is multiplied by 2)



And 3x=12 is the same as



x=4 (everything is divided by 3)

Answer 4

K. Well in keeping with the orders of operation- you have to do exponents first. So three to the 2nd vigour is 9 and 3 to the 1/3 power is 27. You've got now 9+2 x 27. Next, you ought to do multiplication. So 2 x 27 is fifty four. You are now left with 9+54 which is 63!