If x=-5/8 and y=-1/2, what is the value of the expression -2 x-y^2?

1 (C). We first note the values of x and y as given.

GMAT Functions: If x=-5/8 and y=-1/2, what is the value…

If x = - \frac{5}{8} and y = - \frac{1}{2}, what is the value of the expression - 2 x - y^{2} ?

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Explanation	Calculations	Help
$We first note the values of x and y as given.$	$x = - \frac{5}{8} y = - \frac{1}{2}$
$We substitute these values into the expression.$	$- 2 x - y^{2} = - 2 \times (- \frac{5}{8}) - (- \frac{1}{2})^{2}$
$We simplify the product in the first term and reduce the fraction.$	$- 2 \times (- \frac{5}{8}) = \frac{- 2 \times- 5}{8} = \frac{2 \times 5}{2 \times 4} = \frac{5}{4}$
$We simplify the square of the fraction in the second term.$	$(- \frac{1}{2})^{2} = \frac{( - 1 ) ^{2}}{2 ^{2}} = \frac{1}{4}$
$We subtract the simplified terms using a common denominator.$	$\frac{5}{4} - \frac{1}{4} = \frac{4}{4} = 1$

1 (C)