Question

Solve the system, using substitution.

4x + y = 4 and y = 4 - 4x

A. no solution
B. infinitely many solutions

I put A is this correct?

Answer 1

YES

Answer 2

No, that is incorrect. The answer is B.

Answer 3

Im getting mixed signals...

Answer 4

there are infinite solutions

Answer 5

lol. since 4=4 i don't think there is infinite solutions

Answer 6

$$(x,y) = (1, 0)$$ is an answer.

Answer 7

as is $$(x,y)=(1/2, 2)$$.

Answer 8

nomothetis how did you get this ?

Answer 9

I am getting a little MORE confused... ^_^ lol so many diff answers!!

Answer 10

just try some

(x,y) = (0.5, 2) is another solution

Answer 11

:P sorry i am retaking stuff from like the beginning of the year :P So then do u all agree with jimmy?

Answer 12

Here's how you prove that you have an infinite number of solutions: Can you make get equation 2 by multiplying equation 1 by something? Let's consider it:

$$4x + y = 4$$

This is the same thing as:

$$y = 4 - 4x$$

Since all we need to do is pass the x to the other side. So the two equations are really the same equation. So any points that is a solution for the first equation will work for the second equation. But if you look at the first equation, you see that it's the equation for a line. Therefore, any point on that line will be a solution to the second equation as well. This means that you have an infinite number of solutions.

Answer 13

oh nomo siad that one

try
(x,y) = (0.25,3) then!!!

Answer 14

Ok so its B?!?!?! are we positive on this answer now? lol

Answer 15

i don't agree since it clearly states that "solve by substitution"

Answer 16

B) is correct, even if you use substitution. The substitution gives 4=4 which means that the statement is always true for any (x,y) as long as (x,y) is on the line 4x+y=4.

Answer 17

right nomo - the 2 equations are the same and u can fit infinite values of x and corresponding values of y into the equation

Answer 18

ok i see. that makes sense watchmath

Answer 19

absolutely positively b !! lol

Answer 20

Okay!! haha finally!! (: lol