Question

8. Calcule o valor das expressões
numéricas:
5
a)
4
(9) +2.(4)
b) (3) (+)-(+)61
c) (-0,28) · (+1,5) - (+0,7) · (-0,72)
d) 0,625 - (+0,84). (+0,6)​

Answer 1

Olá!

Vou responder as que eu entendi ok

b)

$\left(3\right)\left(+\right)-\left(+\right)\cdot \:61\\\\=3-\left(+\right)\cdot \:61\\\\=3-61\\\\=-58$

c)

$\begin{pmatrix}-0&28\end{pmatrix}\begin{pmatrix}1&5\end{pmatrix}-\begin{pmatrix}0&7\end{pmatrix}\begin{pmatrix}-0&72\end{pmatrix}\\\\=140-\begin{pmatrix}0&7\end{pmatrix}\begin{pmatrix}-0&72\end{pmatrix}\\\\=140-504\\\\=-364$

d)

$0.625-\left(0.84\right)\left(0.6\right)\\\\=0.625-0.84\cdot \:0.6\\\\=0.625-0.504\\\\=0.121$

Espero ter ajudado, só falta a letra A, tenha boas aulas!