Question

For questions 5-7, find the solution to the system of equations by using either graphing or substitution.

6. y=2x-1 and y=x+3
A. (4, 7)
B. (7, 4)
C. (-7, -4)
D. Infinite Solutions

Answer 1

so you have
$$
2x-1=y\\
\color{blue}{x+3=y}\\
---------
$$

Answer 2

I believe the answer is A.... Is that correct?

Answer 3

well, what would you need in the "blue" or bottom equation, to have it substract from the top and get "x" by itself?

Answer 4

Idk... I'm not very knowledgeable about algebra.

Answer 5

well, I assume you were given this because it has already being covered by the textbook, and you're supposed to know it

Answer 6

otherwise, you shouldn't be doing it

Answer 7

Mhm. And I have been trying to figure out the solution my textbooks solution is just a little complicated for me to understand..

Answer 8

lemme retype the equations some

Answer 9

$$
2x-1=y\\
\color{blue}{x\ +\ 3=y}\\
---------\\
\color{blue}{x\ +\ ?=\ ?}\\
$$

Answer 10

you'd want the 2nd equation, the bottom one, to "turn into" something that when added to the top one, gives only one variable, and cancels out the other

Answer 11

so you may end up with something like

3x+5=0, or 0+8=y, or so

Answer 12

for this instance, so you can see it, try
$$
2x-1=y\\
\color{blue}{x\ +\ 3=y} \ \ \times (-1)\\
---------\\
\ \ \ 2x-1=y\\
\color{blue}{-x-3=-y}\\
---------\\
$$
? - ? = ?

Answer 13

add them both "vertically", what do you get?