During a substitution method, I worked my math and got -15/7 for my x-value. I checked the back of my book and it gave a whole number for x? Did I do something wrong?
Problem: x=-2y x=2-4y
(Use Substitution Method)

Question

During a substitution method, I worked my math and got -15/7 for my x-value. I checked the back of my book and it gave a whole number for x? Did I do something wrong?
Problem: x=-2y    x=2-4y
(Use Substitution Method)

skullpatrol · Answer

What did you do?

anonymous · Answer

Woops the problem was x=3y-4 and 2x-y=7 *Sorry*
I plotted in the equation x=3y-4 into 2x-y=7. I got 2(-3y-4)-y=7. I distrubted and then got -6y-8-y=7. Then, I combined like terms getting 7y=15. Using the multiplicative property, I then got y=-15/7 as the book says its -2.

skullpatrol · Answer

What does the question ask for?

anonymous · Answer

It tells us to solve the following equations using the substitution method. The back of the book wants the ordered pairs from both equations.
Examples: x=y-1, y=4-2x  ----> (1,2)

skullpatrol · Answer

$$\huge 	ext{I got } 2(-3y-4)-y=7.$$ The minus sign /|\ here infront of 3y is not suppose to be there.

anonymous · Answer

Wow I was blind from that. Thanks! You really saved my time! c:

skullpatrol · Answer

Thanks for trying to understand .