The ages of two students A andB are 19years and 15years respectively find how many years it will take so that product of there ages becomes equal to 480
Answers
Answer:
=480-15+19
=480-34
=446/2
=223
A=223-19
=242
B=223+15
=228
Step-by-step explanation:
He have to wait 223 years
Answer :
It will take 5 years for the product of the student's ages to be 480
Step-by-step Explanation :
Given : Age of A = 19 year's
Age of B = 15 year's
To find : how many years it will take so that product of tere ages become equal to 480 = ?
Let x be the number of years til the product of their ages is 480. Then,
( 15 + x ) × ( 19 + x ) = 480
285 + 15x + 19x + x² = 480
x² + 34x = 480 - 285
x² + 34x = 195
x² + 34x - 195 = 0
Use the quadratic formula,
x = -b +-√b²- 4ac/ 2a
Where,
a = 1
b = 34
c = -195
Substituting the given value in above formula
We get,
x = -34 +- √ (34)²-4×1×(-195) / 2×1
x = - 34 +- √ 1936 / 2 ( just simplifying )
x = -34 + 44 / 2. OR. x = -34 - 44/2
x = 10 /2 = 5. OR x = -78 / 2 = -39
Since age can't be negative so x = 5 year's
So, It will take 5 years for the product of the student's ages to be 480