Question

i have 2 questions 1 is what is z if 3[z=7]=-12 and number 2 what is y if [4-2y]+5=9

Answer 1

$3|z+7|=-12\\|z+7|=-4\\\\z+7=-4\\z+7=4\\\\z=-11\\z=-3\\\\\\\sf{Plug~them~to~test~if~the~solution~is~correct.}\\\\ 3|-3+7|=-12 \\ 3 (4)\neq -12 \\ \\ 3 |-11+7|=-12\\ 3 (4)\neq-12 \\ \\ \\ \boxed{\sf{There~is~no~solution.}}$ $|4-2y|+5=9\\|4-2y|=4\\\\4-2y=4\\4-2y=-4\\\\y=0\\y=4\\\\\\\boxed{\sf{The~solution~is~y=0~and~y=4}}$