Question

I need help solving an equation using the "u"
|2-2t|+1=7

Answer 1

I'm not sure what you mean by using the "u" but solving this I would do this:
|2-2t|+1=7
|2-2t|=6
2-2t=6 and 2-2t=-6
-2t=4 and -2t=-8
t = -2 and t = 4

Answer 2

the U is "union" and is translated into english as "or"

Answer 3

TBates use of the word "and" is mathematically an error; we might say that in common english, but in math-speak -2 union 4 is -2 or 4.

Answer 4

the algebraic work above is correct, but absolute value equations are translated using the union or U.

Answer 5

Ah, that makes sense. Most of the time I write x = -2, 4 and the comma is generally regarded as being "or" anyway but I suppose "mathematically grammatically" I should use union of sets to give the answer.

Answer 6

think of it this way: what is the intersection of the sets {-2} and {4}?
answer= null set

compared to the union of {-2} U {4}?
answer= {-2, 4}

Answer 7

liljenredd, you will use U or union or "or" anytime you have an absolute value equation, or absolute value expression > positive number;

when you have abs. values expression < positive number you will use "and" or intersection

Answer 8

the U sub

Answer 9

i don't understand you roast post "sub"?

Answer 10

no roast but last!!!!!!

Answer 11

I understand
I was just telling Tbates what I was trying to type

Answer 12

do you want an example?

Answer 13

but you all are right

Answer 14

sure

Answer 15

can you show me how you got that answer

Answer 16

Example: solve |2x-3| > 6

(solution to follow on next post)

Answer 17

by definition of absolute value

-(2x-3)>6 or 2x-3>6

2x-3<-6 or 2x-3>6
2x<-3 or 2x>9 (add 3 to both sides of both inequalities)
x<-3/2 or x>9/2 (divide by 2)

the graphical solution isthe interval notation is\[(-\infty, -3/2) \cup (9/2, \infty)\]