Question

$I.\frac{12\times 4}{x^{4/7}}-\frac{3\times 4}{x^{4/7}}=x^{10/7}$
$II.y^3+783=999$

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

Answer 1

The correct option is E x = y or the relationship cannot be established

Equation I
$\frac{12\times 4}{x^{4/7}}-\frac{3\times 4}{x^{4/7}}=x^{10/7}$
$\Rightarrow 48-12=(x{)}^{10/7}\times (x{)}^{4/7}$
$\Rightarrow 36=(x{)}^{\frac{10+4}{7}}=(x{)}^2$
$\therefore x=\pm 6$
Equation II
$y^3+783=999$
$\Rightarrow y^3=999-783$
$\Rightarrow y^3=216$
$\therefore y=\pm 216$
$\therefore x=y$