Question

3x+2y=23
x+5z= -7
2y-z+16

How do you do this??? PLEASE HELP

Answer 1

Some substitution should do the trick:
From equation 2:
x = -7-5z

Answer 2

i know you use substitution but i still get stuck T.T

Answer 3

Plugging that instead of x into equation 1 gives us:
3(-7-5z) + 2y = 23, a bit of simplification will give us:
-21-15z+2y=23
-15z+2y=23+21
-15z+2y=44

Answer 4

By the way is the third equation this:
2y-z=16 (= instead of +)

Answer 5

Hello?

Answer 6

oh srry let me try it out hold on

Answer 7

oh no it is +

Answer 8

hello???

Answer 9

@bahrom7893

Answer 10

It must have been a typo, that's impossible to solve otherwise.

Answer 11

so what do i do after i plugged in the x?

Answer 12

ohh no no yes yes it is = i was looking at the wrong + SORRY

Answer 13

so what do i do now? its narrowed down to -15z+2y=44 now what?

Answer 14

@bahrom7893

Answer 15

Plugging that instead of x into equation 1 gives us:
3(-7-5z) + 2y = 23, a bit of simplification will give us:
-21-15z+2y=23
-15z+2y=23+21
-15z+2y=44

From the third equation find z:
2y-z=16
2y-16=z
z=2y-16

Plugging this into the equation above:
-15(2y-16)+2y=44

Answer 16

Solve for y, then find z, then find x

Answer 17

z = 2y-16
x = -7-5z

Answer 18

how do i solve for y though? i f i keep having two variables???

Answer 19

OHH wait wait nvm i get it i get it haha okay let me solve the whole thing and see if i get an answer :) THANK YOU SO MUCH :)

Answer 20

Go for it :)

Answer 21

I got the answer! It's 8 :) and it was one of the choices! Thank you! :) Do you mind helping me again later??? :)

Answer 22

@bahrom7893