. Two years ago, a man's age was three times the square of his son's age. In three years' time
his age will be four times his son's age. Find their present ages.
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let age of man be x years
age of his son be y years
so,
two years ago,
x-2=3(y-2)^2 -----(i)
three years after,
x+3=4(y+3)
X+3=4y+12
x=4y+9 -----(ii)
now, put the value of x from eq.ii in the eq.i.
x-2=3(y-2)^2
4y+9-2=3(y^2+4-4y)
4y+7=3y^2+12-12y
4y+12y+7-12=3y^2
16y-5=3y^2.
3y^2-16y+5=0
3y^2-15y-1y+5=0
3y(y-5)-1(y-5)=0
(3y-1)(y-5)=0
from it we get,
y=1/3 ( not possible)
and y=5
so, sons age is 5 years
and for man age put value of y in eq.ii
x=4y+9
x=(4x5)+9
x=29 years.
I hope this is helpful to you ☺️
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