Question

SOMEONE PLEASE HELP ME
Solve the system of equations by substitution. What is the solution for x?
2x + y = 1

4x + 2y = -1 (1 point)

Question 2 options:

1) x = 0
2) x = 2
3) There is no x value as there is no solution.
4) x can be any value as there is an infinite number of solutions.

Answer 1

@KlOwNlOvE

Answer 2

@SolomonZelman

Answer 3

well.. if you solve the 1st equation "2x + y = 1" for "y", what would that give you?

Answer 4

y=2x+1

Answer 5

@jdoe0001

Answer 6

well.... hmmm how did you transfer the 2x over to the right side?

Answer 7

ohhh I ment that as a negative sowwy
y=-2x+1

Answer 8

@tHe_FiZiCx99

Answer 9

@jdoe0001

Answer 10

woops got a bit caught up... yes is y = -2x+1 well then, now we know what "y" is equals to so \(\bf 2x + {\color{brown}{ y}} = 1\\
4x + 2{\color{brown}{ y}} = -1
\\ \quad \\ \quad \\
2x + {\color{brown}{ y}} = 1\implies {\color{brown}{ y}}=-2x+1\qquad thus
\\ \quad \\
4x + 2{\color{brown}{ y}} = -1\implies 4x + 2{\color{brown}{ (-2x+1)}} = -1\)

so if you solve that for "x"... that'd give you what "x" is
and then you can plug that in eihter equation, to solve for "y", to see what "y" is as a constant

Answer 11

hmmm I get a funny result on that one

Answer 12

\(\bf 4x + 2{\color{brown}{ y}} = -1\implies 4x + 2{\color{brown}{ (-2x+1)}} = -1\implies \cancel{ 4x-4x }+2=-1\)

but... well obviously \(\large +2 \ne -1\) <--- so that's not really a valid EQUATion