today’s class was very interesting( like always) and in the same time nothing was new.

we start the class by Mr. k, saying that tomorrow is the

*pretest*and

*Tuesday no school*and

*Thursday the test*,

and that we have sub teacher.

So here is what was going on in the class. We did some questions for solving for X.

-solve for x:

1) (9)/(x+2)=(5)/(7) {don't forget the instruction} X≠ -2, -7

7x=5(x+2)

7x=5x+10

7x-5x=10

2x=10

x=5 (always check your answer before moving to another question because it will help to you sure that your answer is right and it will also help you to remember the restrictions( Because it might remind you if you forgotthe restriction or write it wrong so you can fix it.)

2) (4)/(x)+(3)/(2x)=(11)/(4) X≠ 0

{Find the less common denominator that will divide the other denominator evenly.}

(16)/(6)=(11x)

(22)=(11x)

2=x check your answer

3) (x-1)/(x+1)+(3)/(x-1)=1 X≠ + or - 1

the common denominator is (x-1)(x+1)

(x-1)(x-1)+3(x+1)=(x-1)(x+1)

(X^2)-(2x)+(1)+(3x)+(3)=(X^2)-(1) balancing the equation (both have x^2 both side, so they reduce.)

X+4=-1

X=-5 Check your answer

Mr. K gave as some helping steps we could use:

1. Always see if you could factor any thing.

2. Write the restrictions.

3. Check your answer.

4) (7)/(3x-12)+(1)/(4 -x)=(2)/(3) X≠ 4

(7)/3(x-7)+(1)/(4 -x)=(2)/(3)

(7)/3(x-4)+(1)/-(x-4)=(2)(3) the common denominator is 3(x-4)

The negative sign could move from between -(x-4) and change the + sign to -.it’s like having.

(7)/3(x-4)-(1)/(x-4)=(2)(3) {t he common denominator will reduce.}

7-3=2x-8

12=2x

6=x

Mr. K finish by saying: "math is science of patters. Nothing is new in this unit accept the factoring and divide and the restrictions."

And then we start some word problem.

Recall: Distance= (RATE)(TIME)

Nicole and Jaindrive in opposite directions. After 3 hours they are 360KM apart. If Nicole’s rate is 10KM/K faster than Jian’s rate, how far did Jain travel?

Nicole___________________& _____________ Jian

10KM/K -----------------------------360--------------------

Jians’s Rate =x (if you don’t know something, then it isX)

Nicole’s Rate= x+10

We used the Magical triangle Distance

Rate_________Time

3x+3(x+10)=360 (3 is the hours)

3x+3x+30=360

6x=330

x=55

The second question was:

Natasha can mow a lawn by herself in 1.5 hours. Steve can mow the same lawn is 2 hours. If they work together mow how long will it take to mow the lawn?

If Steve work 1 lawn in 2 hours then:

(1 lawn)/(2 hours)= (x lawn )/(1 hours)

1=2X

½ =x

Natasha: (same thing but different number)

(1 lawn)/(3/2 hour)=(x lawn )/(1 hours)

1=3/2 x

2/3=X

Finally our home work is Exercise number 53, and omit 11,12,14

The scrib for tomorrow is K.M.

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