Question

Evaluate 7(7x - y - 9) for x= -4 and y= -2

Answer 1

@Whitemonsterbunny17 :)

Answer 2

So, first, we replace x with -4, and y with -2.

Answer 3

okay,
7(7{-4} - {-2} - 9)

Answer 4

Mhm, so according to PEMDAS, what is next? (:

Answer 5

the parentheses! :)

Answer 6

\(\large\frak\color{lime}{Yep!}\) :D

Answer 7

Now, this part is a bit more complicated.

Answer 8

Basically, it is the same as this ({7-4} + {-2 + -9})

Answer 9

okay, so
7(-28 - -11)
?
it got confusing at the -2 and 9, but hopefully i did it right :)

Answer 10

Let's start by just looking at the first part of it: {7-4}.
Just subtract 4 from 7, because 7 is a positive number, and 4 is negative, so it is the same as subtracting 4.

Answer 11

7-4=3 :)

Answer 12

Yep! (:
Now let's look at the second part.
{-2 = -9}
Just add 2 + 9 and put a negative symbol in front!

Answer 13

so -11

Answer 14

Yes.

Answer 15

So now, that section would look like this:
{3-11}

Answer 16

All you have to do now for that is find 3-11

Answer 17

okay, but you wouldn't mind me asking a question? i actually made it look like this:
7(3 - {-11}) which would give me a different answer than 3 - 11. could you please explain so that i can completely understan? :)

Answer 18

That would still give you the same answer.

Answer 19

oh, so a postiive 3 minus a negative 11 is the same exact thing as 3 - 11 ?

Answer 20

Yes, because the 3 is already positive, and a -11 is the same as subtracting 11.

Answer 21

ohh thank you! i have a difficulty with adding/subtracting negatives and positives haha. but back to where we were?

Answer 22

Oh, after we finish solving this problem I can try to help you understand adding\subtracting negatives and positives better. :3

Answer 23

sure! that would be great!

Answer 24

Awesome! :3
So, now, we figure out what 3-11 is.

Answer 25

okay 3-11 = -8

Answer 26

Yep! :D

Answer 27

So now, our problem looks like this: 7(-8)

Answer 28

okay now we just multiply 7 and -8 ?

Answer 29

Yes.

Answer 30

so that would be -56

Answer 31

\(\large\frak\color{lime}{Correct!~\bigstar}\)

Answer 32

So, does that all make sense? (:

Answer 33

Yup! :)

Answer 34

would you be able to help me with adding and subtracting negatives and positives now? :)

Answer 35

Sure! Maybe open a new question, and tell me what you don't understand about it. (:

Answer 36

ok!