Question

how come teacher dont use pemdas on equation like 4(3x+7)-2(8x-3)

Answer 1

how else would they do it

PEMDAS
parenthesis- you cant add variables to constants, so we ignore this
exponents- there are none
multiplication- this can be done, you would have to distribute the 4 and distribute the -2
division- also none exists
addition- add like terms
subtraction- subtract like terms

Answer 2

for example on a question 1/2(3x-8/6)-1/3(x-6/4)-(3x+3/4) the teacher got -11/6x-11/12. wouldn't it be 3.5/3x-11/12

Answer 3

4(3x+7)-2(8x-3
12x + 28 - 16x + 6
-3x + 34

Answer 4

er one sec

1/2(3x-8/6)-1/3(x-6/4)-(3x+3/4)

3/2x - 8/12 -1/3x +6/12 -3x -3/4

3/2x-2/3 -1/3x +1/2 -3x -3/4

9/6x -2/6x-18/6 x -8/12 +6/12 - 9/12

11/6 x -11/12

Answer 5

oops sorry its -11/6x -11/12

Answer 6

but aren't suppose to follow PEMDAS

Answer 7

i did follow pemdas

Answer 8

1/2(3x-8/6)-1/3(x-6/4)-(3x+3/4)
starting with this

P-i cant add the terms within the parenthesis so i leave the problem as is
E- no exponents
M- multiplication = distributing all the terms which would give me

3/2x - 8/12 -1/3x +6/12 -3x -3/4

D- no division

then i just changed the fractions around so they have a common denominator which allows me to combine like terms easier

9/6x -2/6x-18/6 x -8/12 +6/12 - 9/12

then i did A & S - combined like terms


-11/6x -11/12

Answer 9

so, do you get it?

Answer 10

this is how the teacher did it
1st she simplify to get 3/2x-8/12-1/3x=6/12-3x-3/4
then she simplify -1/3x and -3x together 1st since she told us it would be easier wouldn't it be 3/2x +-1/3 first

Answer 11

oh, so your question has to do with order in which you add things

it doesnt matter in what order you add things up

its called the commutative property of addition and associative property of addition

so the commutative property of addition lets us rearrange terms when you're adding/ subtracting them

so
A+B= B+A
or
A+B+C+D+E= A+B+C+E+D = A+B+D+E+C= E+D+C+B+A= ... etc

now the associative property of addition
says that it doesnt matter in which order you add multiple terms

Associative property of addition

(A+B)+C= A+(B+C) = (A+C)+B

or

Answer 12

ok thank you so much.
I got so confuse

Answer 13

yup no prob

hopefully you understand this now