This week we learned how to solve systems algebraically with more than one variable.
For example: x+6y=4 and 0=x-4y
In these types of systems you used steps.
- Isolate a variable
- Plug the equation for that variable into the second system
- solve for that variable
- plug variable into original equation, solve for the missing variable
This may not make complete sense in steps, so I’ll demonstrate using the first example.
- x+6y=4 can be rearranged to make x=4-6y
- next you plus your new equation x=4-6y into your second equation: 0=x-4y which turns into 0=(4-6y)-4y. This becomes y=2/5.
- Next, we plug our value for y into our original first equation x+6y=4, which becomes x+6(2/5)=4
- Simplifying the equation: x=1.6
- Check y=2/5 and x=1.6: x+6y=4 -> 1.6+6(2/5)=4 Yes! 0=x-4y -> 0=1.6-4(2/5) Yes! So we know we did it correctly