Simplify the following : 1. 4(x-y) + 3(x-y)
2. 8(p-q) + 3(p-q)
3. 8(x+y) - 4(x-y)
4. 7(x+y) - 4(x-y)
5. 6(p+q) - 4(p-q)
6. 5(x-y) - 4(x-y)
7. 8(p-q) - 3(p-q)
8. ax+3bx+ay+3by
9. 2ax-6ay+bx-3by
10. mp-4np+mq-4nq
11. 3xr+3xs-yr-ys

Factories the following:
1. -8pq+24pr+32ps
2. -10ra+25rd+35rc
3. -5ra-10rd+15rc
4. 81ab+27ac+3bad
5. -5lx+15ly+25lz
6. -9ab+36ac+45ad​

Lin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. she knows that the total cost to download 3 videos was $12. her work to find the equation is shown below. joylin’s work step 1 k= 3/12= 0.25 step 2 y= 0.25x where did joylin make her first error?