Question

I will fan


Solve the following system of equations by using elimination
1.) -x+y=7
X+y=1
2.) 5x-2y=24
3x+2y=24

Answer 1

Fan and metal

Answer 2

let's start with the first one

-x+y=7
x+y=1

let's try adding these equations together!

what is -x + x?

Answer 3

0

Answer 4

good! what is y + y?

Answer 5

2

Answer 6

not quite!

hint: A + A = 2A
y + y = ?

follow the pattern

Answer 7

So 2y

Answer 8

great! next step is to add 7 + 1 = 8

therefore: 2y = 8

what does y equal?

Answer 9

8

Answer 10

not quite!

we know that "2y" is equal to 8. but what about "y" by itself?

Answer 11

4

Answer 12

good! so y = 4

now, we can go back to our original equations

if x + y = 1, AND y = 4, then what is x?

Answer 13

1

Answer 14

not quite!

x + y = 1

therefore

x + 4 = 1

__ + 4 = 1

fill in the blank

Answer 15

-5

Answer 16

getting warmer but not quite

Answer 17

hint: subtract 4 from both sides

1 - 4 = ?

Answer 18

3

Answer 19

not quite...

Answer 20

use a calculator if you are unsure

Answer 21

0

Answer 22

nope, try again

Answer 23

use this calculator: https://www.google.co.uk/?gfe_rd=cr&ei=3WBAWN_0B-zR8gfOxIOoAg#q=calc

Answer 24

type in "1 - 4"

Answer 25

-3

Answer 26

good job!


so our answer for #1 is (-3,4)

lets move on to problem 2!

Answer 27

5x-2y=24
3x+2y=24

again, we can add these together

3x + 5x = ?

Answer 28

8x

Answer 29

good job!

now what is -2y + 2y?

Answer 30

0

Answer 31

great job! next step is to add 24 + 24 = 48

now we have

8x = 48

what does "x" equal?

Answer 32

28

Answer 33

8 * ____ = 48

fill in the blank

Answer 34

6

Answer 35

good, so x = 6

next step:

we know that 3x+2y=24
if we substitute x into the equation we get

18 + 2y = 24
so, we can subtract 18 from both sides to get

2y = 6

what does "y" equal?

Answer 36

3

Answer 37

good so the answer to #2 is (6,3)