Question

equação de primeiro grau

a + b = 48
a = 3b
​

Answer 1

Resposta:

$3b+b=48\\\\\mathrm{Subtrair\:}b\mathrm{\:de\:ambos\:os\:lados}\\\\+b-b=48-b\\\\\mathrm{Simplificar}\\\\a=48-b\\\\\\a=3d\\\\\\3b+b=48\\\\\mathrm{Somar\:elementos\:similares:}\:3b+b=4b\\\\4b=48\\\\\mathrm{Dividir\:ambos\:os\:lados\:por\:}4\\\\\frac{4b}{4}=\frac{48}{4}\\\\\mathrm{Simplificar}\\\\b=12$