Question

(y + 8)^2 - (у + 9)(у - 5) = 117

Answer 1

(у + 8)² - (у + 9)(у - 5) = 117
у² + 16у + 64 - у² - 4у + 45 = 117
12у = 117 - 109
12у = 8
у = 2/3

Answer 2

$(y+8)^2-(y+9)(y-5)=117 \\ y^2+16y+64-(y^2+9y-5y-45)=117 \\ y^2+16y+64-y^2-9y+5y+45=117 \\ 12y+109=117 \\ 12y=117-109 \\ 12y=8 \\ y= \frac{8}{12}= \frac{2}{3}=0.(6)$