Answer:
1. y=6
2. x=-2
3. t=-6
Step-by-step explanation:
1.
[tex]4y-9=15\\4y-9+9=15+9\\4y=24\\\frac{4y}{4}=\frac{24}{4}\\y=6[/tex]
2.
[tex]6x+7=-5\\6x+7-7=-5-7\\6x=-12\\\frac{6x}{6}=\frac{-12}{6}\\x=-2[/tex]
3.
[tex]-9t+2=56\\-9t+2-2=56-2\\-9t=54\\\frac{-9t}{-9}=\frac{54}{-9}\\t=-6[/tex]