If 15(2x^2 - y^2) = 7xy find x:y if x and y both are positive
Answers
Answered by
67
Sol :
Given 15( 2x2 - y2 ) = 7xy
⇒ 30x2 - 7xy - 15y2 = 0
⇒ 30x2 - 25xy + 18xy - 15y2 = 0
⇒ 5x(6x - 5y) + 3y(6x - 5y) = 0
5x + 3y = 0 and 6x - 5y = 0
5x = -3y and 6x = 5y
x / y = -3 / 5 and x / y = 5 / 6.
x : y = -3 :5 or 5 : 6.
Given 15( 2x2 - y2 ) = 7xy
⇒ 30x2 - 7xy - 15y2 = 0
⇒ 30x2 - 25xy + 18xy - 15y2 = 0
⇒ 5x(6x - 5y) + 3y(6x - 5y) = 0
5x + 3y = 0 and 6x - 5y = 0
5x = -3y and 6x = 5y
x / y = -3 / 5 and x / y = 5 / 6.
x : y = -3 :5 or 5 : 6.
Answered by
3
Answer:
15(2x² - y²) = 7xy
30x²-15y² = 7xy
30x²-7xy-15y²=0
30x²-25xy+18xy-15y²=0
5x(6x-5y)+3y(6x-5y)=0
(5x+3y)(6x-5y) = 0
5x+3y = 0 or 6x-5y=0
5x = -3y or 6x = 5y
x/y = -3/5 or 6/5 = y/x
x/y = 5/6
x:y =5:6
we will ignore x/y = -3/5 as both numbers are given positive and a negative vaue will not come in answer
Similar questions