hw #2-R2 Due Thurs(A)/Fri(B) Oct 27/28

**HAND-IN:**

**Problem Set C #17, 23**

A) Complete Chapter 2 Problem Set C

Finish all problems EXCEPT the following: 1,4,7,

**13**,14,15,17
(#13 is from section 2-5... go ahead and try!!)

Give me a proportion bar model for #22-24

B) Complete Chapter 1 Booster Practice Worksheet

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Chapter 2 Test with Chapter 1 Booster

Thursday, October 27th (A) and Friday October 28th (B)

In the Problem Set C solving equations practice packet on problem #5, the answer I get is -6=x but the answer key says 6=x. I also checked with someone else and they got -6=x too. Our we wrong or is there a typo?

ReplyDeleteI'm glad you're asking, since errors do occur in answer keys.

DeleteThe next question that you're likely to ask me is "Do we have to check our answers on the test?" I am allowed to make a bet that you didn't check this answer?

Notice that you didn't state the problem... I guess since I'm not too busy, I'll state the problem:

-2 = [(2x)/3] - 6

Let's check your answer of x=-6

-2 ?=? [(2(-6))/3] - 6

-2 ?=? [(-12)/3] - 6

-2 ?=? [(-4)] - 6

-2 ?=? -10

NOPE, -2 aint = -10... hmmm... I wonder what would happen if you checked x=6?

How could we have solved correctly?

-2 = [(2x)/3] - 6 ... Add 6 to both sides

4 = [(2x)/3] ... Mult both sides by 3

12 = 2x ... Divide both sides by 2

6 = x

hmmmm... should I let you check this solution?

Mr.C, you made a mistake. You did -2[(-4)]-6 not -(-6).

DeleteActually, I stated the problem wrong.... I thought it was "- 6" at the end instead of "- x"... that's why I need you guys to state the problem when you blog...

DeleteDo we have to do problem 17 again?

ReplyDeleteYup... sorry, I want you to hand it in...

DeleteEven though I'm not in this class anymore, I still have a question. What is a linear expression??????????????

ReplyDeleteDear QQ,

DeleteStop by anytime!! A linear expression (and usually we will discuss it as a linear equation) is generally an expression in one or two variables where the variable(s) is raised to the first power only.

When you graph a linear equation in the coordinate plane, you will graph a straight line, hence the moniker "linear."

Linear expressions

x + 5

x + y

Linear equations graph as a straight line

y = x + 5

x + 2y = 10

Hope this helps!

I need help with problems 5 (-2=2x/3-s), 8 (1/3(42-18h)=2(8-4h), and 11 (26.4x-3.2=5.9x-32.1

ReplyDeleteFor number 11, use a calculator and round the answer up to the hundredths. Even though the check step will give you non equivalent answers, (since it is off by a couple thousandths), the answer is still right. For number 5, you still have to ask Mr. C.

DeleteI would have like to know your first step... and WOW, look at that, you stated #5 wrong this time... must be a toughie!!

Delete#5. -2 = 2x/3-x

Two possible first steps:

1) Mult both sides by 3 (FRAC-ATTACK!)

2) re-write as -2 = (2/3)x - (3/3)x

#8. (1/3(42-18h)=2(8-4h)

A first step of Distribution should do it, right... try that and let me know

#11. 26.4x - 3.2 = 5.9x - 32.1

Simlar to a FRAC-ATTACK, multiply both sides by 10

Watch this 5-minute video... I actually solve a similar problem two different ways.

Lmk if this helps.

Do we do problem 16 on problem set C even though we did it for the hand in for the last homework?

ReplyDeleteOops... sorry... whatever...

DeleteOn #20 I was confused with using the Cross Product Property. when You multiply the extremes what would that equal. The problem is w^2+3/2w+2=w/2. Thanks

ReplyDeleteClearly, after a CPP you getsk:

Deletew(2w+2) = 2(w^2+3)

next... distribute and/or do an area model... you'll getsk:

2w^2 + 2w = 2w^2 + 6

Hint: Will the Sub POE allow you to subtract 2w^2 from both sides... you bet your sweet bippie it will!!

lmk if this helped...

Thank you so much Mr. C now I get it. Yay

DeleteThat helped me too Mr.C

DeleteI need help on problem 12 (15x+3-10x=5x)

ReplyDeleteJust combine like terms on the left side... then just keep staring at it...

DeleteWill 5x + 3 ever be equal to 5x??

They will always be 3 units apart, yes? Never to meet again... a romantic math tragedy!!

Somebody should write a joke short story based around that. A math based romance/tragedy... I'm sure that it would be a hit! XD

Deleteagreed!!

DeleteI also need help with problem 17, convert 9 gallons/sec to quarts/minute

ReplyDeleteMaybe you can look at the MathChamber videos. Remember the conversion rates are that 4 quarts = a gallon, and 60 seconds = a minute.

DeleteThanks, Amarie. Agreed. This is a very typical rate conversion problem (see a video). We start (on the left) with gallons over seconds, with a target (to the right) of quarts over minutes.

DeleteThen, you simply "stage" the conversion factors (see Amarie's note above) so that the gallons divide out and the quarts come in (qt/gal) and so that the seconds divide out and the minutes come in (use secs/mins)... capeesh??

I need help on number 6 which is 3x + 3/2(2x-1=2, please.

ReplyDeleteI'm having trouble with problem 20, (w^2+3/2w+2 = w/2). After a lot of math, I get to 2w^2 = w^4 +w. What do I do from here or what did I do wrong?

ReplyDeleteapparently you write to the blog, but you don't read it... scroll up just a little for my response...

DeleteI am still having trouble with this problem. It is problem set C number 5. I got x=-6 and when I checked I got that too. Idk whether I am making a rly stupid mistake or what. The problem is...

ReplyDelete-2=[(2x)/3]-x

Try multiplying both sides by 3 (you'll have to distribute on the right) and lmk what happens...

DeleteHi mr c, i'm really confused on #19 on problem set c. the question is: (x+2)/(2x-6)= 3/8. I multiplied each side by 6, and i got x=10.5. Help!

ReplyDeleteWhy wouldn't you use the cross product property?

DeleteHave you watched this MathChamber Academy video... it was labeled as a 2-7 video "examples:...

there are three examples in this video... fast forward to the third, I think that will help...

lmk...

http://www.screencast.com/t/avAjDTwe1C

My father and I don't agree on a step i took in a problem i did, he thinks 1/4*3x is thee fourths x. but i think that it's 3x/4 can you help?

ReplyDeleteAh-hh Algebra, bringing families together while tearing them apart!!

DeleteWell, depending on how you look at it, you're either both right or both wrong.

(1/4)*3x

could be written as either (3/4)*x or (3x)/4

let's do the humpty-dumpty

(1/4)*3x can be split to (1/4)*(3/1)*(x/1) right?

Since this is all multiplication, we can order it and group it anyway we want. Either way, both of your expressions are correct. So one could argue that you're both wrong for not recognizing that you're both right!! I LOVE MATH!!

Did this help?