Question

 

dada a matriz ache o valor de a e b  

 

2a+1        2b+2      =      9        -4

ab+a        2a+b²            -8        17

 

Answer 1

é só igualar todos os termos:

 

$<var>\left[\begin{array}{cc}2a+1&2b+2\\ab+a&2a+b^{2}\end{array}\right] = \left[\begin{array}{cc}9&-4\\-8&17\end{array}\right]</var>$

 

$\begin{cases} 2a+1=9\\2b+2=-4\\ab+a=-8<var>\\2a+b^{2}=17</var>\end{cases}</var>$

 

2a+1=9 => a=(9-1)/2 => a=4

2b+2=-4 => b=(-4-2)/2 => b=-3

 

ab+a = 4*(-3)+4 = -12+4 = -8 (confere)

2a+b² = 2*4+(-3)² = 8+9 = 17 (confere)