A pair of equations is shown below:

y = 2x − 1
y = 4x − 5

Part A: In your own words, explain how you can solve the pair of equations graphically. Write the slope and y-intercept for each equation that you will plot on the graph to solve the equations. (6 points)

Part B: What is the solution to the pair of equations? (4 points)

Question

A pair of equations is shown below:

y = 2x − 1
y = 4x − 5

Part A: In your own words, explain how you can solve the pair of equations graphically. Write the slope and y-intercept for each equation that you will plot on the graph to solve the equations. (6 points)

Part B: What is the solution to the pair of equations? (4 points)

anonymous · Answer

@Michele_Laino @thekefentse

ddcamp · Answer

You want a point (x,y) that is on both of those lines. This point will be where the two lines intersect. What would you do to find the intersection by graphing them?

michele_laino · Answer

hint:
we can solve your system using the elimination method, namely, we make equal each other, the right sides of both equations

michele_laino · Answer

so we can write:
$$2x - 1 = 4x - 5$$

michele_laino · Answer

please solve that equation for x

anonymous · Answer

x=2

michele_laino · Answer

that's right!
nevertheless you need a graphical solution, I'm sorry for my misunderstand

anonymous · Answer

its ok. do you know how it can be put in as a graph?

michele_laino · Answer

yes!

anonymous · Answer

yea!

michele_laino · Answer

for example, let's consider the first equation:
y=2x-1

michele_laino · Answer

if we set x=0, I get:
y=2*0-1=...?

anonymous · Answer

-1

michele_laino · Answer

ok! so the firs line passes at point (0,-1)

michele_laino · Answer

furthermore, if I set y=0, then I can write:
0=2*x-1
what is x?

anonymous · Answer

1/2

michele_laino · Answer

ok! so our first line passes at points:
A=(0,-1) and B=(1/2,0)

anonymous · Answer

yea thank you. medal of course. also i have one more question and ill stop bugging you.

michele_laino · Answer

now we can draw it as below:
|dw:1429983186675:dw|

anonymous · Answer

I just saw this. Never got any notification :/

anonymous · Answer

hmm i put it there. i think. sorry.

michele_laino · Answer

now, let's consider the second equation:
y=4x-5
again if I set x=0, I get:
y=4*0-5=...?

anonymous · Answer

I see it. I'm new to this site, how/where do notifications work

anonymous · Answer

there will be a little sign that has a number over it and it will say someone tagged you.

anonymous · Answer

topish left corner of page

anonymous · Answer

ah! I see it go off now.

anonymous · Answer

y=-5

michele_laino · Answer

ok!
so the second line passes at point P=(0,-5)
now, I set y=0, so I can write this:
0=4x-5
what is x?

anonymous · Answer

5/4

michele_laino · Answer

ok! so the second line passes at points:
P=(0,-5), and Q=(5/4,0)

michele_laino · Answer

here is the drawing of both lines:
|dw:1429983780630:dw|