Question

This equation shows how the number of bread plates that Joseph has left is related to the number of tables that he has set. p = -4t + 45 The variable t represents the number of tables Joseph has set, and the variable p represents the number of bread plates remaining. How many tables does Joseph need to set in order to have just 5 bread plates left to distribute?

Answer 1

1st: you would plug in 5 as p. your equation would be 5=-4T+45. 
2nd: subtract 45 from both sides so that it cancels out. 5-45=-4T+45-45
3rd: simplify. -40=-4T
4th: divide by -4 so that it cancels out. -40/-4=-4T/-4
4th. simplify. 10=T
you can check your answer by plugging in 10 for T. p=-4x10+45
P would equal 5 so T equals 10