Question

Simultaneous equations:
6 = b√ 2
3a = b

How can I find a?

Answer 1

\[6=b \sqrt{2}\]

divide both sides by sqrt 2

then you have b
plug it in the 3a = b
then divide both sides by 3
now you have a

Answer 2

What happens to 6 in the first equation when both sides are divided by sqrt 2? Why is only b left?

Answer 3

What you have to get is that algebra is like a set of scales. Whatever you do to one side of an equation you do to the other, and the only way to solve for a is to find b.
We know 6 = b *sqrt(2). We want b by itself, to do that we get rid of the sqrt(2). By dividing both sides of the equation by sqrt(2) it leaves b= 6/(sqrt(2))

Answer 4

b= 6/(sqrt(2))
so plug it in the 2nd equation

3a = 6/(sqrt(2)) divide both sides by 3, now you have a

Answer 5

Oh, got it! Thank you :)