How do you solve this one step equation that looks like n-6=-9 with work

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

2/3(-6y+9x) expand each expression using the distributive property

One number is 4 less than 3 times a second number. if 3 more than two times the first number is decreased by 2 times the second number, the result is 11. use the substitution method. what is the first number?