Question

VALENDO 20 PONTOS!!!
O valor da soma x + y + w + z de modo que, $\left[\begin{array}{ccc}x&y\\z&w\\&&\end{array}\right]$ + $\left[\begin{array}{ccc}-3&-4&\\5&-2&\\&&\end{array}\right]$ = $\left[\begin{array}{ccc}8&0&\\7&-6&\\&&\end{array}\right]$, é:
POR FAVOR COM CÁLCULOS


a) 21

b) 23

c) 29

d) 11

e) 5

Answer 1

Some os elemento de mesma posição e igual a outra matriz:

$\left[\begin{array}{ccc}x&y\\z&w\\\end{array}\right] + \left[\begin{array}{ccc}-3&-4\\5&-2\\\end{array}\right] = \left[\begin{array}{ccc}8&0\\7&-6\\\end{array}\right] \\\\\\\left[\begin{array}{ccc}x-3&y-4\\z+5&w-2\\\end{array}\right] = \left[\begin{array}{ccc}8&0\\7&-6\\\end{array}\right] \\\\\\x - 3 = 8\\x = 8 + 3\\x = 11\\\\y - 4 = 0\\y = 4\\\\z + 5 = 7\\z = 7 - 5\\z = 2\\\\w - 2 = - 6\\w = - 6 + 2\\w = - 4 \\\\\\x + y + w + z = 13$

Resposta: Nenhuma das alternativas.

Answer 2

Explicação passo-a-passo:

=> Valor de x

x - 3 = 8

x = 8 + 3

x = 11

=> Valor de y

y - 4 = 0

y = 4

=> Valor de z

z + 5 = 7

z = 7 - 5

z = 2

=> Valor de w

w - 2 = -6

w = -6 + 2

w = -4

Assim:

x + y + w + z = 11 + 4 + 2 - 4

x + y + w + z = 15 - 2

x + y + w + z = 13