Can i get help please

My favorite songstress gives away 25% of this side of her signature fragrance collection to her charity last month her sales were 1200 how much of her sales did she donate

Find an bif a = {3, 6, 9, 12) and b = {2, 4, 6, 8, 10).

The value of x in this system of equations is 1. 3x + y = 9 y = –4x + 10 substitute the value of y in the first equation: combine like terms: apply the subtraction property of equality: apply the division property of equality: 3x + (–4x + 10) = 9 –x + 10 = 9 –x = –1 x = 1 what is the value of y?