( 0.5 * ( K - C ) ): ( C^2 + D^2 ) = 24
2x - 21 + 6x = 3
8x = 24
x = 3
12 - x = 20 - 10x + 10
9x = 20 - 12 + 10
9x = 18
x = 2
A) 2x+4≠0 2x≠-4 x≠-2
D(y)=(-∞;-2)U(-2;+∞)
b) (4+x)(x-2)≠0 4+x≠0 x≠-4 x-2≠0 x<span>≠2
D(y)= (-</span>∞; -4)U(-4;2)U(2;+<span>∞</span>)