Algebra: A Combined Approach (4th Edition)

$y^{2}$ -7
(-7$y^{2}$ + 5 ) - ( -8$y^{2}$ + 12 ) -7$y^{2}$ + 5 + 8$y^{2}$ - 12 ( -7$y^{2}$ + 8$y^{2}$ ) + ( 5 - 12) combine like terms $y^{2}$ - 7 simplify