Question

Substitution help??
Solve using substitution:
3y − x − 1 = 0
- 4x = -6y
Select one:
a. No solution
b. Infinitely many solutions
c. (7, 8/3)
d. (1, 2/3)

Answer 1

I'm going to start off by solving 3y - x - 1 = 0 for x

Answer 2

3y - x - 1 = 0

3y - x - 1+x = 0+x ... Add x to both sides.

3y - 1 = x

x = 3y - 1

Answer 3

Now that we have isolated x, we can plug that into equation 2


-4x = -6y

-4(3y - 1) = -6y ... replace x with 3y - 1


making sense so far?

Answer 4

yes yes

Answer 5

are you able to solve -4(3y - 1) = -6y for y?

Answer 6

9=y right?

Answer 7

incorrect

Answer 8

-4(3y - 1) = -6y

-12y + 4 = -6y

4 = -6y + 12y

4 = 6y

y = ???

Answer 9

-2? Sorry I suck at math..

Answer 10

you divide both sides by 6 to isolate y

Answer 11

.6

Answer 12

0.6 repeating, that is equal to 2/3

Answer 13

so y = 2/3

Answer 14

then you take this solution for y and plug it into -4x = -6y

then solve for x

Answer 15

awesome bro thanks

Answer 16

np