Question

solve the system by the method of substitution
5x-y=5
5x-3y=15
Options
A-(0,-5)
B-(-5,0)
C-(5,1)
D-(1,5)
Please show work
thanks
PLEASE HELP ME??????

Answer 1

first solve equation 1 for y
5x-y=5
y=5x-5
is it ok till now

Answer 2

the second one would be y=5/3x-5

Answer 3

you do not need the second one now . just follow me
is this ok with you.?
first equation is
5x-y=5
y becomes
y=5x-5
tell me .

Answer 4

yea

Answer 5

ok

Answer 6

but i forget how do u change those types of problems the one that is 5x-y=5

Answer 7

ok first equation is

5x-y=5
add y to both sides
5x-y+y=5+y
5x=5+y
now subtract 5 from both sides
5x-5=5+y-5
5x-5=y
y=5x-5
i hope it is clear now .
now put the above value of y in the second equation at the place of y
5x-3y=15
since
y=5x-5
5x-3(5x-5)=15
5x-15x+15=15
-10x=0
x=0/10
x=0
is it ok till now ?

Answer 8

yea

Answer 9

put x=0 in the any of the given equation and tell me the value of y

put in the first one x=0
5x-y=5
tell me y value.

Answer 10

y=-5

Answer 11

so the answer is a

Answer 12

yes .you are genius !!
well done ..

Answer 13

thnks i wouldnt be a genius if it wasnt for u

Answer 14

I was just going to say why not just let

5x = 5x and set
5 + y = 15 + 3y

Answer 15

wat

Answer 16

Both equations have 5x, so you can isolate 5x in each

Answer 17

yea u could do that

Answer 18

yes @Hero you are right. there always more than one way to solve the question.
you can subtract the two equations as well .
at least right now i know more than seven methods by which it can solved !! :)

Answer 19

Yes, that's great.