Yeah, sometimes the time is blown out by stopping to think about if I am getting things right up until that point (because I’m surprised by the results), or catching a mistake while checking my answers in the equations and having to redo bits. These ones that don’t have fractions are easier. But I’ve been doing some practise with fractions and it’s still quicker. Knowing that I should clear the fractions first helps. I was kind of trying to combine steps before but separating them is working better.
can you figure out how to extend it to work with 3 equations and 3 variables?
I think I would:
- clear any fractions
- rearrange e.g equation 3 for variable a
- substitute that into equation 1 and 2 and simplify so they are expressed only in terms of b and c
- rearrange e.g equation 2 for variable b
- substitute that into equation 1 and solve for c
- substitute c into equation 2 and solve for b
- substitute b and c into e.g equation 1 and solve for a
It kinda seems like that’d work? It’s kind of hard to tell just typing and I’ll probably figure out more once I try one with more equations. Maybe also there is a better to way to summarise the method. I think you need an equation per variable.