Question

blue line is Y=x/2 -1 and green line is Y=2x+1 where do the lines cross ?

Answer 1

Y = Y
x/2 -1 = 2x+1
2x-x/2=-1-1
3x/2 = -2
3x = -4
x = -4/3

Answer 2

The lines cross where the two equations are equal:

\[\frac{x}{2}-1=2x+1\]

Can you solve that equation?

Also, have you tried graphing these lines with geogebra or your calculator?

Answer 3

put that x = -4/3 in any equation to get y comp.

Answer 4

Let.
blue line=red line
Y=Y
x/2-1=2x+1
x/2=2x+2
x=4x+4
x-4x=4
-3x=4
x=-4/3\
Answer=-4/3

Answer 5

Here is the graph.

Answer 6

You can create that graph by going to http://www.wolframalpha.com and typing in "plot y = x/2 -1 and y = 2x+1" (without the quotes).

Answer 7

thanks for the help !