Question

3 years ago my brother was twice as old as my sister. Now he is 12 years older than she is. How old is my sister now?

Answer 1

bros age=x
sister age =y

(x-3)=2y
x=y+12
solve now

Answer 2

TeX version of it.
\[
\begin{align*}
(x-3)&=2y \\
x+12&=y
\end{align*}
\]

@lalaly \(x=y+12?\) That doesn't seems to be correct but I am not sure.

Answer 3

it looks right although i'm not too sure

Answer 4

hes 12 years older than his sister
means his age= sisters age+12

Answer 5

im sure:)

Answer 6

I think that lalaly is right (: Thank you

Answer 7

Yes you are right. @lalaly

Answer 8

:):)

Answer 9

correct nice job