# Challenge 398: Squarely Simultaneous

Here's a pair of uncommon simultaneous equations to solve...

(i) Given that 15x^{2} - 18xy + 3y^{2} = a(bx-y)^{2} - c(x + y)^{2} for all values of x and y, determine the values of a, b and c.

(ii) Find all pairs of values (x, y) that satisfy the simultaneous equations

(1) 15x^{2} - 18xy + 3y^{2} = 0

(2) 10x^{2} - 16xy + y^{2} + 5 = 0