math

can someone correct this for me...
solve:
-4(2x - 3) = -8x + 5

my answer:
this equation has no solution because they don't equal

i get 0=-7

-4(2x-3)=-8x+5

-8x+12=-8x+5

0(x)=-7

So am I correct

You are right, let me explain a bit more.

When you write down:

-4(2x - 3) = -8x + 5

you actually say: Suppose there exists an x such that
-4(2x - 3) equals -8x + 5

Then, assuming this is true, you attempt to find, using some manipulations ,the value of x. If you find a value for x, then you should still check if the equation is satisfied, although this last step is often skipped.

But in this case you find a contradictory statement:

0 = -7

This statement is false, which means that the orginal assumption that there exists an x such that
-4(2x - 3) equals -8x + 5
must be false.

To see this let's take statement A to be: "There exists an x such that
-4(2x - 3) equals -8x + 5"

And let's take statement B to be:
"0 = -7". Let's forget for a minute that statement B is obviously false.

Using Algebra you have shown that if A is true then B must be true. In such a case you can also conclude that if B is not true, then A must be false. So, if you know B to be false, then you know that A must be false because if A were true then B must be true which you know isn't the case.

  1. 👍 0
  2. 👎 0
  3. 👁 123

Respond to this Question

First Name

Your Response

Similar Questions

  1. Algebra 2

    1. Solve the following for x. 3-(x+(-4))= 2x-6+5x I figured that the answer is no solution. Is this correct? I have been working with my friend on this next problem and neither of us know which is correct. 2. Solve for r.

    asked by Christian on August 30, 2007
  2. Algebra

    Hi this question was already asked but there is still no correct answer. I can't seem to solve this for x correctly...I got 128 over 55 as an answer which can't be correct. Please help me find the correct answer! Thanks The

    asked by Clare on October 12, 2011
  3. drbob222 math,correction

    i made some corrections for the previous postage can you check those when you get a chance please. Also for this one: my options of answers are: A)2y + 6/3 B)3x- 6 /2 C)2 + 2y D)2/3y + 6 Directions: Solve for x: 3x - 2y =6 3x - 2y

    asked by jasmine20 on January 11, 2007
  4. Algebra

    Can someone verify if my answers are correct? Solve. 1/x+6-1/x-6 My answer is: -12/x^2-36 Solve. 1/x+5+2=5/x+5 My answer is: -3 Subtract. Express your answer in simplest form. 13x/30-4x/15 My answer is: x/6 Can someone verify if

    asked by Need Help on July 12, 2007
  5. Math Inequalities

    -9/8x greater than or equal to -1/16 can someone please check my answer? my answer is x greather than or equal to 1/18 is this correct? if not what is the correct answer and what is the correct way to solve this problem..maybe I

    asked by Anna on November 5, 2009
  6. Algebra

    Solve. x-3/15=1/3 I get 8 as an answer. Is this correct? If you substitute 8 for x, you'll find that 8 is not the correct answer. x - 3/15 = 1/3 x = 3/15 + 1/3 x = 3/15 + 5/15 x = ______ Please post your answer and a teacher will

    asked by Linda on July 12, 2007
  7. Algebra

    I can't seem to solve this for x correctly...I got 128 over 55 as an answer which can't be correct. Please help me find the correct answer! Thanks! The equation is: .05x-.6(x+2)=.08 Please show the work as well as the answer.

    asked by Clare on October 12, 2011
  8. business math

    Of the 4800 students at Medium Suburban College (MSC), 50 play collegiate soccer, 60 play collegiate lacrosse, and 96 play collegiate football. Only 6 students play both collegiate soccer and lacrosse, 6 play collegiate soccer and

    asked by liz c on November 14, 2010
  9. Algebra

    I'm not sure if I have this correct I have to solve each literal equation for the indicated variable. A=1/2h(B+b)variable is (b). I have the answer as: 2A=h(B1+b2) 2A/h=B1+b2 (2A/h)-b2=B1 Is this correct? weren't you supposed to

    asked by ms jay on August 9, 2007
  10. math,correction

    okay for the first one i/ve done it twice and both times i got 10, not -10. check your work to make sure you did it correctly. for the second one i got 24 so you are correct Directions solve for x. (x)/(x-2)-(x+1)/(x)=(8)/(x^2-2x)

    asked by Marie on February 25, 2007
  11. math,correction,plz

    can someone correct this forme solve 7/5 = 35/x My answer: x = 25 solve x/2 minus x/3 = 3 My answer: x = 18 Both are correct

    asked by jasort20 on March 14, 2007

More Similar Questions