Linear Simultaneous
1. Stating the problem: Plot the graph of the system of linear simultaneous equations:
$$y-2x=5$$
$$2y+x=0$$
2. Rearrange each equation in terms of $y$:
From the first equation:
$$y=2x+5$$
From the second equation:
$$2y=-x \implies y=\frac{-x}{2}$$
3. These two equations represent two lines:
Line 1: $$y=2x+5$$
Line 2: $$y=\frac{-x}{2}$$
4. To find their intersection, solve the system:
Set their $y$ values equal:
$$2x+5=\frac{-x}{2}$$
Multiply both sides by 2 to clear the fraction:
$$4x+10=-x$$
Add $x$ to both sides:
$$5x+10=0$$
Subtract 10:
$$5x=-10$$
Divide by 5:
$$x=-2$$
5. Substitute $x=-2$ to find $y$:
Using first equation:
$$y=2(-2)+5=-4+5=1$$
6. The lines intersect at the point $(-2,1)$.
This means the system has a unique solution.
7. For the graph, plot the lines:
Line 1 passes through $(0,5)$ and $(1,7)$.
Line 2 passes through $(0,0)$ and $(2,-1)$.
Plotting these lines will show their intersection at $(-2,1)$.