Question

Determine o valor de x, sabendo que a média aritmética ponderada de 2x-4 com peso 3 e 2x+8 com peso 2 é igual a 20.​

Answer 1

$\Large\boxed{\begin{array}{l}\sf\dfrac{ 3\cdot(2x-4)+2\cdot(2x+8)}{3+2}=20\\\\\sf\dfrac{6x-12+4x+16}{5}=20\\\\\sf\dfrac{10x+4}{5}=20\\\\\sf 10x+4=5\cdot20\\\sf 10x+4=100\\\sf 10x=100-4\\\sf 10x=96\\\sf x=\dfrac{96}{10}\\\\\huge\boxed{\boxed{\boxed{\boxed{\sf x=9,6}}}}\end{array}}$