intermediate algebra

tell me did i figure it out
divide
2/5/-1/2
2/5/-2/1
answer -4/5


-12+7^2-(7)*2
-12+49-7*2
-12+42*2
-12+84
answer 72 is this correct
 
hopen2impov said:
-2 + (-6)
-2 - 6 = -8 would this be correct when adding two negatives Yes.



for multiplication, if you have two negative it's a positive sign Yes, a negative times a negative is positive.



5^2*(-10) + (-11)*8
5^2*(-10) - 11*8
25*(-10) - 11*8
-250 - 88
answer -338, is this correct? Yes.



4m^2 - 2mn + 3n^2 - 8(2m^2 + 4mn - 9n^2)
4m^2 - 2mn + 3n^2 - 8 + 2m^2 + 4mn - 9n^2 This line is not correct.

If you want to remove the parentheses, then you need to follow the Distributive Property. That means each term inside the parentheses gets multiplied by -8.

 
hopen2impov said:
evaluate (3x - 6x^2)/(x^2 - 10) for x = -1

(3*x - 6*x*x)/(x*x - 10)
(3*[-1] - 6*[-1]*[-1])/([-1]*[-1] - 10)
(-3 - 6)/(-10)
18/(-10) This line is not correct; subtracting 6 from -3 does not give 18.

 
hopen2impov said:
(2/5)/(-1/2)
(2/5)/(-2/1) You did not change the division sign to a multiplication sign.

This line should be (2/5)*(-2/1)


answer -4/5 This result is correct.




-12 + 7^2 - (7)*2
-12 + 49 - 7*2
-12 + 42*2 This line is not correct.

The Order of Operations says that you must multiply (7*2) before subtracting.

 
ok, here's the problem you gave me to try,

7(3a^2+2ab-4b^2)+5(-2a^2-3ab+b^2)
21a^2+14ab-28b^2+-10a^2-15ab+5b^2
simplify
+21a^2+14ab-28b^2
-10a^2 -15ab+ 5b^2
answer 11a^2-ab+23b^2 I was trying to figure out +14ab-15ab would it be -ab or will it just cancel out of the math problem to -10^2+5b^2
 
To all the professionals that's helping me, i want to say "thank you" so very much. I haven't done math, in over 20 years. I never learned algebra. I dropped out of hight school before i got to learn it. It's difficult to remember every thing but i am trying and willing to get this algebra, i even take notes on what you teach me. This is some type of math and i just wanted to say "I APPRECIATE YOU AND WILL CONTINUE TO NEED YOU" :)
 
Here's one you was helping me with,

(3*x-6*x*x)/(x*x-10)
(3*[-1]-6*[-1]*[-1])/([-1]*[-1]-10)
(-3-6)/(-10)
(-9)/(-10)
answer -9/10
 
hopen2impov said:
ok, here's the problem you gave me to try,
7(3a^2+2ab-4b^2)+5(-2a^2-3ab+b^2)
21a^2+14ab-28b^2+-10a^2-15ab+5b^2
simplify
+21a^2+14ab-28b^2
-10a^2 -15ab+ 5b^2
answer 11a^2-ab+23b^2 I was trying to figure out +14ab-15ab would it be -ab or will it just cancel out of the math problem to -10^2+5b^2
answer 11a^2-ab+23b^2 : not quite; 11a^2 - ab - 23b^2 ; just a sign error; good work!

14ab - 15ab = -ab ; STOP there!
14ab - 14ab would cancel out; see that?
 
hopen2impov said:
(3*x-6*x*x)/(x*x-10)
(3*[-1]-6*[-1]*[-1])/([-1]*[-1]-10)
(-3-6)/(-10) The denominator is not -10.
(-9)/(-10)
answer -9/10

Hi there:

You got the numerator correct. Now, let's focus on the denominator: x^2 - 10

When x = -1, we have (-1)^2 - 10.

With practice, you will recognize this as 1 minus 10, but, for now, if you need to write out the multiplication explicitly, that's okay.

(-1)(-1) - 10

1 - 10

-9

So, the denominator is -9.

I'm thinking that you wrote [-1][-1]-10 and then subsequently read it as [-1][-1][-10].

In other words, you mistook the subtraction sign to be a negative sign, so you multiplied by -10 instead of subtracting positive 10.

I've seen you make this error before. Be careful with the operations; don't change them.

The final answer is -9/(-9), which is 1.

Cheers ~ Mark 8-)
 
I'm starting to understand it mark, thank you! Do you know math problem, something i never learned regarding algebra?
 
clear fractions or decimals, solve and check

3/2(2x+5)= -15/2
2/3*3/2(2x+5)= -15/2
2x+5= -15/2*2/15
2x+5-5= -5
2x=-5
-2+2x=-5-2
x= 7 is this correct?
 
hopen2impov said:
clear fractions or decimals, solve and check

3/2(2x+5)= -15/2
2/3*3/2(2x+5)= -15/2 * 2/3
2x+5= -15/2* 2/3
2x+5-5= -5 - 5
2x= -10

2x/2 = -10/2

x = -5



-2+2x=-5-2
x= 7 is this correct? No

The nature of mistakes you are making - is worriesome to me. Please seek out a face to face instructor to teach you fundamental mechanics of algebra.
 
I have tried looking for a face to face instructor but i can not afford one. I said i have never learned algebra. This site was recommended to me by a friend. If you don't want to help me could you please get someone who has the patience to help me. I'm trying hard to get this myself but i am trying to get this, not cause worry to you. I really need the help. I can't quit college, i come too far.
 
hopen2impov said:
Do you know math problem, something i never learned regarding algebra?

I do not understand this question. Can you rephrase it ?

Are you taking college classes online ?

Does your college offer any free tutoring services on campus ?

 
hopen2impov said:
1.5*(-2.3)*5
-3.45*5 =
answer -17.25

(-55.7) + 27.6 + (-3.4)
-55.7 + 27.6 - 3.4
-28.1 - 3.4
answer -31.5

2/5 - 1/2
the only way i know how to do this is to divide by the LCD.
is the answer -1/10 by finding the LCD and add.
2/10 - 1/10 = -1/10 if this isn't correct, i don't know!

\(\displaystyle ***\)

\(\displaystyle Note:\) Your answer is correct, but your work is wrong.
You can multiply and divide by 10 at the same time:

\(\displaystyle (\frac{10}{10})(\frac25) - (\frac{10}{10})(\frac12) = \frac{1}{10}(\frac{20}{5} - \frac{10}{2}) = \frac{1}{10}(\frac{4 - 5}{1}) = -\frac{1}{10}\)



simplify

-12 + 7^2 - (7)*2
-12 + 7^2 - 14
-12 + 49 - 14
61 - 14
answer 47 is this correct

\(\displaystyle ***\)\(\displaystyle No, -12 + 49 -14 = 37 - 14 = 23\)

5^2*(-10) + (-11)*8
25*(-10) - 11*8
-250 - 88
-338 is this correct?

\(\displaystyle *** Yes.\)

5*(-8 - 1) + 3*(-7)
5*(-9) + 3*(-7)
-45 - 21
answer -66 is this correct?

\(\displaystyle *** Yes.\)

4*(2 + 3)^2 - 3*(5 - 3)^2
4*(5)^2 - 3*(2)^2
4*25 - 3*4
100 - 12
88 is this correct?

\(\displaystyle *** Yes.\)

what in the world!

4m^2 - 2mn + 3n^2 - 8(2m^2 + 4mn - 9n^2)

\(\displaystyle Note:\) The exponents are on the variables, not also the coefficients.
The expression inside the parantheses does not get altered until the \(\displaystyle -8\)
is distributed to all of the terms inside and the parentheses dropped.

\(\displaystyle 4m^2 - 2mn + 3n^2 - 16m^2 - 32mn + 72n^2\)

\(\displaystyle (4m^2 - 16m^2) + (-2mn - 32mn) + (3n^2 + 72n^2)\)

\(\displaystyle -12m^2 -34mn + 75n^2\)


4m^2 - 2mn + 3n^2 - 8(4m + 4mn - 81n)
4m^2 - 2mn + 3n^2 - 8(8m^2n - 81n)
4m^2 - 2mn + 3n^2 - 8(-73m^2)
16m - 2mn + 9n - 8(-73m^2)
14mn + 9n - 8(-73m^2)
23mn^2 - 8(-73m^2)
15mn^2(-73m^2)
-1095m^3n oh please tell me if this brain buster is correct?

\(\displaystyle ***No.\)
Look at the suggested steps above.

\(\displaystyle Note:\) Also, type spaces between your plus and minus signs,
and between the number/expression and the equals sign for
1) improved readability, and 2) to cut down on your mistakes by seeing
more clearly what is presented to you.
 
simplify, but no negative exponents in the answer.

24x^-5yz^2/8x^2y^4z
answer 3x^-5yz^2/x^2y^4z, is this correct, i divided by 8 and subtracted the exponents.
 
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