Question

Will give Medals and Fan!!!! Use the substitution method to solve the following systems of equations. Write the solution as an ordered pair, and show all work.

x+y=5 and y=x-7

Answer 1

Quick answers please!

Answer 2

subsiitute the second equation y=x-7 into the first
x+ y =5

x+(x-7) =5

solve this for x

Answer 3

Thanks!

Answer 4

what do you get?

Answer 5

....

Answer 6

after you find x , back-substitute to find y

Answer 7

@iCreeperrr

have you worked out x?

Answer 8

no... I forgot how xD

Answer 9

it would be simplified to x-7x=5 right?

Answer 10

x+y = 5 and y = x-7

x+(x-7) = 5
x+x-7 = 5

Answer 11

what is x+x?

Answer 12

x^2

Answer 13

nope x times x is x squared ,

by x + x = (1+1)x
=

Answer 14

2x.

Answer 15

that's better

Answer 16

so you have

x+(x-7) = 5
x+x-7 = 5
2x - 7 =5

now add seven to both sides

2x - 7 + 7 = 5+ 7

what does this simplify to ?

Answer 17

x+(x-7)=5
x+x-7=5
2x-7=5
2x=12
x=6

right?

Answer 18

thats right
you have found x,

now we can find y

Answer 19

then substitute that into the other equation

Answer 20

y=6-7
y=1

Answer 21

remember the second equation was

y = x-7

so y = 6 -7

Answer 22

almost, but 6-7 is not equal to 1

Answer 23

-1 I meant xD

Answer 24

haha thats better,

Answer 25

Thanks for the help, its been a while since I learned this and I don't have my book with me.. :l

Answer 26

so you have x=6 and y=-1

if we check these in the original equations they should work

x+y=5 and y=x-7

6+ -1 = 5 ? -1 = 6-7 ?

if theses are both true we have correctly solved for x and y

Answer 27

That's what I got :)

Answer 28

goood

Answer 29

now to write the solution as an ordered pair

just write the solution in the form (x, y)

Answer 30

(6,-1)

Answer 31

√