Question

$I.x^2+3x-28=0II.y^2-y-20=0$

• A. $x=y$or relationship cannot be established
• B. $x>y$
• C. $x<y$
• D. $x\ge y$
• E. $x\le y$

Answer 1

The correct option is A $x=y$or relationship cannot be established

Equation I
$x^2+3x-28=0$
$\Rightarrow x^2+7x-4x-28=0$
$\Rightarrow x(x+7)-4(x+7)=0$
$\Rightarrow (x+7)(x+4)=0$
$\therefore x=-7,4$
Equation II
$y^2-y-20=0$
$\Rightarrow y^2-5y+4y-20=0$
$\Rightarrow y(y-5)+4(y-5)=0$
$\Rightarrow y(y-5)+4(y-5)=0$
$\therefore y=-4,5$
Hence, relationship cannot be established.