Answer:
goldfish is 15 and guppies is 11
Explanation:
Given data
let the number of goldfish be x
and the number of guppies be y
so
x+y= 25----------1
and
3x+4y= 86-------2
solve 1 and 2
x+y= 25
3x+4y= 86
from 1
x= 25-y
put this in 2
3(25-y)+4y= 86
75-3y+4y= 86
75+y= 86
y= 86-75
y=11
put y= 11 in 1
x+11= 26
x= 26-11
x= 15
Hence goldfish is 15 and guppies is 11