Y=-9x+8 y=-10x+9 I don't know how to solve this

You use substitution, so you chose one of the equations to plug in, let's use y=-9x+8 you plug that in where it says y because that is what y equals. So the new equation is - 9x+8=-10x+9. After that you add 10x to both sides and the equation breaks down to x+8=9 and finally x=1

x = 1

Step-by-step explanation:

From the various available methods of solving systems of linear equations, let's use substitution, because "y = " appears in both equations:

y = - 9x + 8 = y = - 10x + 9

Then - 9x + 8 = - 10x + 9

Combining the x terms, we get:

x + 8 = 9

Finally, subtracting 8 from both sides yields

x = 1