Question

Hallar el valor de "y", si: 1 + 3 + 5 + 7 +... + (2y+3) = 289

PORFA NO RESPONDAN SI NO SABEN

Answer 1

Respuesta:

1 + 3 + 5 + 7 +... + (2y+3) = 289   y = 135

Answer 2

SERIES NOTABLES

Fórmula:

$1+3+5+7+...+(2n-1)=n^{2}$

Problema:

$1 + 3 + 5 + 7 +... + (2y+3) = 289$

Igualamos:

$2n-1=2y+3\\2n=2y+3+1\\2n=2y+4\\n=y+2$

$n^{2} =289\\n=17$

$y+2=17\\y=15$