Find a common solution for each system of equations.?

Question

y= X -1
y= 2x - 5

Answer 1

You have two equations for y, so equate them:

x - 1 = 2x - 5

Now subtract x from both sides:
-1 = x - 5

Add 5 to both sides:
4 = x

So x = 4

Answer 2

2x -5 = x -1
x = 4

y = 4 -1
y = 3

Check:

3 = 4 - 1 and 3 = 8 - 5
3 = 3 adn 3 = 3

Answer 3

y= x -1
y= 2x - 5

We can rewrite y=x-1 as x = y+1
Now substitute this into y = 2x - 5
so
y = 2(y+1) - 5
y = 2y + 2 - 5
y = 2y - 3
y - y = 2y - y - 3
0 = y - 3
y = 3

Since we know x=y+1
x = 3+1
x = 4

So the common solution is x=4, y=3