Question

Calcule o valor das expressoes

Answer 1

$2x-y= \\ \\ 2.7-(- \frac{1}{2} )= \\ \\ 14+ \frac{1}{2} = \\ \\ \frac{28+1}{2} = \frac{29}{2}$

$x^{2} -yz= \\ \\ ( \frac{1}{2} )^2- \frac{1}{2} . \frac{1}{4} = \\ \\ \frac{1}{4} - \frac{1}{8} = \\ \\ \frac{2-1}{8} = \frac{1}{8}$