Secondary III • 3yr.
How to solve this with the comparison method:
y = 3x + 2
y = 5x-24
How to solve this with the comparison method:
y = 3x + 2
y = 5x-24
Explanation from Alloprof
This Explanation was submitted by a member of the Alloprof team.
Hi!
I'm not going to solve it for you, but what I suggest is that I do a detailed example of how to use this method. You can then apply it on your own to solve that problem.
Let's try to solve this:
$$y+3x=5 \: \:\: and \:\:\: y= 2x+9$$
1. First, you have to isolate the same variable in your two equations. Let's isolate y (you could have isolated x too)
$$y=5-3x \: \: \: and \: \:\: y= 2x+9$$
2. Second, we want to have a single variable in an equation. We will set y = y
$$y=y$$
$$Therefore, \: 5-3x = 2x+9$$
3. Third, we must find the variable x by isolating it.
$$5-3x = 2x+9$$
$$5-9 = 2x+3x$$
$$-4= 5x$$
$$\frac{-4}{5}=x$$
4. Finally, replace the result of x in one of our two initial equations. We can also replace it in both the equations if we want to verify our answer. Indeed, the result of y should be the same whether you replace the x in the first or in the second equation.
$$y= 2x+9$$
$$y= 2\frac{-4}{5}+9$$
$$y= 2\frac{-4}{5}+9$$
$$y= \frac{37}{5}$$
Hope this helped you. If you have other questions, do not hesitate.
Have a nice day!
KH