ICSE Class 10CISCE
Share
Notifications

View all notifications
Books Shortlist
Your shortlist is empty

Divide 20 into Two Parts Such that Three Times the Square of One Part Exceeds the Other Part by 10. - ICSE Class 10 - Mathematics

Login
Create free account


      Forgot password?

Question

Divide 20 into two parts such that three times the square of one part exceeds the other part by 10.

Solution

Let the two parts be x and y.
From the given information,
x + y = 20 ⇒ y = 20 – x
3x2 = (20 – x) + 10
3x2 = 30 – x
3x2 + x – 30 = 0
3x2 – 9x + 10x – 30 = 0
3x(x – 3) + 10(x – 3) = 0
(x – 3) (3x + 10) = 0
x = 3, -10/3
Since, x cannot be equal to -10/3, so, x = 3.
Thus, one part is 3 and other part is 20 – 3 = 17.

  Is there an error in this question or solution?

APPEARS IN

 Selina Solution for Selina ICSE Concise Mathematics for Class 10 (2018-2019) (2017 to Current)
Chapter 6: Solving (simple) Problems (Based on Quadratic Equations)
Ex.6A | Q: 12
Solution Divide 20 into Two Parts Such that Three Times the Square of One Part Exceeds the Other Part by 10. Concept: Quadratic Equations.
S
View in app×