Respuesta :
[tex]\bf \begin{cases} a+b=6\\ \boxed{b}=6-a\\[-0.5em] \hrulefill\\ b+c=-3\\ \boxed{6-a}+c=-3\\ -a+c=-9\\ c=-9+a \end{cases}~\hspace{5em} \begin{array}{llll} a+c=5\\\\ \stackrel{\textit{we know that c = -9+a}}{a+(-9+a)=5}\\\\ 2a-9=5\\\\ 2a=14\\\\ a=\cfrac{14}{2}\\\\ \blacktriangleright a=7 \blacktriangleleft \end{array} \\\\[-0.35em] ~\dotfill[/tex]
[tex]\bf \boxed{b}=6-a\implies b=6-7\implies \blacktriangleright b=-1\blacktriangleleft \\\\\\ c=-9+a\implies c=-9+7\implies \blacktriangleright c=-2 \blacktriangleleft \\\\[-0.35em] ~\dotfill\\\\ a+b+c\implies (7)+(-1)+(-2)\implies 4[/tex]
The value of a+b+c is 4.
What is algebraic expression?
In mathematics, an expression that incorporates variables, constants, and algebraic operations is known as an algebraic expression (addition, subtraction, etc.). Terms comprise expressions.
An algebraic expression in mathematics exists as an expression that is created up of variables and constants, along with algebraic operations (addition, subtraction, etc.). Expressions exist created up of terms.
Given
a+b + b+c + a+c = 6+5-3 = 8
2a + 2b + 2c = 8
so
a+b+c = 4
The value of a+b+c is 4.
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