SOLUTION: I am just beginning with graphing and I am trying to graph y=4x-1 and y=3x+15 to find x. I've solved the equation algebraically but am having a hard time and getting a different ou

Question 104909: I am just beginning with graphing and I am trying to graph y=4x-1 and y=3x+15 to find x. I've solved the equation algebraically but am having a hard time and getting a different outcome each time I graph...and none of them cross at x=16!
I would appreciate any help.
Thanks
Answer by edjones(8007) (Show Source): You can put this solution on YOUR website!
A) y=4x-1
B) y=3x+15
.
Since these graphs are linear we only need 2 points (x,y) for each line. I like to use the x and y intercepts, if fractions don't get involved, because there are less numbers to deal with, so I make less mistakes.
Keep the x and y as small as possible so the points fit on the graph.
.
y=4x-1
x=0, y= -1 (0,-1)
x=1, y= 4-1=3 (1,3)
.
y=3x+15
x= -5 y= -15+15=0 (-5,0)
x= -3 y= -9+15=6 (-3,6)
.
put the points on your graph paper and draw the lines and it should look like this.

The lines do cross do cross when x=16 when y=63 !!! That is the correct answer.
Check:
63=4*16-1 true
63=3*16+15 true
.
Ed
RELATED QUESTIONS
hello, i am trying to do my algebra and i am very lost. I need help graphing the solution (answered by edjones)

I have tried to solve y=2x and I've tried graphing it but it keeps saying I am doing it... (answered by MathLover1,josgarithmetic)

I have the equation y=-x^2-8x-15 and i am trying to graph it. How do I find the... (answered by edjones)

I am trying to solve the linear system of equations by graphing. the problem reads... (answered by mananth)

I have a problem here that I have solved, but now I am having a problem graphing it??? (answered by stanbon)

I am trying to find the quadratic equation for when y=2 and x=... (answered by longjonsilver)

beginning algebra book I am struggling with this equation f(x)=4x-3 find the... (answered by special629)

As a returning adult student, I feel so very stupid. This is from an on line course. The (answered by vleith)

I am trying to figure out graphing. I don't understand why my graphing is different than (answered by checkley71)