Question

1. Solve the following pair of equations by substitution method.
(i) 7x - 15y = 2 ; x + 2y = 3 (ii) 3x – 5y = -1; x-y=-1
3x 5y
(iv) 0.48 +0 31=1 7. n7r
Sy = -2
= -2; X Y Z
L-13
n​

Answer 1

Lets assume x = sqrt(3 + sqrt(3 + sqrt(3 + ………..)))

$\sf \: </p><p>=> x = sqrt(x + 3)</p><p> \\ \\ \sf \: => x^2 = x + 3</p><p>$

$\sf \: => x^2 - x - 3 = 0$

=> x = ( 1 + sqrt(13))/2 OR x = ( 1 - sqrt(13))/2

Since x > 0,

x = ( 1 + sqrt(13))/2 is acceptable answer.