What the the distributive property answer for (-6)(-3)+(-6(3)=(-6)[(-3)+3]

Data from 2005 for various age groups show that for each $100 increase in the median weekly income for whites, the median weekly income of blacks increases by $105. also, for workers of ages 25 to 54 the median weekly income for whites was $676 and for blacks was $527. (a) let w represent the median weekly income for whites and b the median weekly income for blacks, and write the equation of the line that gives b as a linear function of w. b = (b) when the median weekly income for whites is $760, what does the equation in (a) predict for the median weekly income for blacks?

Which one is the correct answer, and why?

Solve the equation: x - 9 = -6 + 5 a. 21 b. 7 c. 14 d. 2