SOLUTION: Byron is 3 years older than doug. The product of their age is 40, how old is Doug?

Question 619534: Byron is 3 years older than doug. The product of their age is 40, how old is Doug?
Answer by Maths68(1474) (Show Source): You can put this solution on YOUR website!
Let
Present age of Byron = b
Present age of Doug = d

Byron is 3 years older than Doug
b=d+3.........(1)
The product of their age is 40
bd=40...........(2)
Substitute the value of b from (1) to (2)
(d+3)d=40
d^2+3d=40
d^2+3d-40=0
Now solve for d
d^2+8d-5d-40=0
d(d+8)-5(d+8)=0
(d-5)(d+8)=0
d-5=0 or d+8=0
d=5 or d=-8
d=-8 (inadmissible)
So d=5
Put the value of d in (1)
b=d+3.........(1)
b=5+3
b=8

Present age of Byron = b = 8 years old
Present age of Doug = d = 5 years old
RELATED QUESTIONS
Doug is twice Anne's age. Doug is 34 years old. How old is... (answered by satyareddy22)

michelle is 19 years older than her brother doug. 6 years fro now, michelle will be twice (answered by scott8148)

Doug is 19 years older than his sister Barbara. In 3 years, he will be twice as old as... (answered by stanbon)

Doug is 12 years older than his sister Linda. in 4 years ,he will be twice as old as... (answered by edjones)

Sally is three years older than helen the product of their age is 54 how old is... (answered by josgarithmetic)

Ana is five years older than Beth.In 5 years, the product of their age is 1.5 times the... (answered by checkley75)

mario is four years older than pedro the sum of their age is 40 how old are... (answered by lenny460)

The sum of David's age and Ben's age is 40. Ann is 3 years older than David. David is 4... (answered by ikleyn)

Darren and Doug must paint the 792-foot fence that encircles their home. Because Darren... (answered by brucewill,richwmiller)