is the following possible? the sum of ages of a mother and her daughter is 25 years . Five year ago the product of their ages was 58
Answers
Let the present age of mother and her daughter be x and y respectively.
Now,
According to the question,
◉ Sum of ages of mother and her daughter = 25
⇒ x + y = 25
∴ x = 25 - y ...(1)
Also,
◉ Five years ago product of thier ages = 58
⇒ (x - 5) × (y - 5) = 58
Substitute x = 25 - y { from (1) }
⇒ (25 - y - 5)(y - 5) = 58
⇒ (20 - y)(y - 5) = 58
⇒ 20y - 100 - y² + 5y = 58
⇒ 25y - y² = 158
⇒ y² - 25y + 158 = 0
Here, Let's find the discriminant to know if the age of daughter would be a real number.
D = b² - 4ac
Comparing the given quadratic equation with the standard form of quadratic equation ( i.e., ax² + bx + c = 0) , we get
- a = 1
- b = -25
- c = 158
⇒ D = (-25)² - 4×1×158
⇒ D = 625 - 632
⇒ D = -7
Here, Discriminant D is less than 0, So No real value is possible, Hence this situation is not possible.
Some Information :-
◉ The standard form of quadratic equation is ax² + bx + c = 0, Where, a≠0 and b & c are constants.
◉ The discriminant D = b² - 4ac, If
- Negative or D < 0
⇒ No Real root exists, But imaginary roots satisfy the equation.
- Equal to 0 or D = 0
⇒ Two real and equal roots exist.
- Positive or D > 0
⇒ Two real and distinct roots exist.
Answer:
I hope this answer will help you.