Answer:
Step-by-step explanation:
Let Brandon's age be [tex]x[/tex]
Therefore Ella=[tex]2x[/tex]
Tristan= [tex]\frac{2x}{3}[/tex]
Fifteen years time add 15 to each age
Brandon: [tex]x+15[/tex]
Ella: [tex]2x+15[/tex]
Tristan:[tex]\frac{2x}{3} +15[/tex]
All their ages together=89
So: [tex]x+15[/tex] + [tex]2x+15[/tex] + [tex]\frac{2x}{3} +15[/tex][tex]=89[/tex]
[tex]3\frac{2}{3} x=44[/tex]
[tex]x= \frac{44}{3\frac{2}{3} } =12[/tex]
