Okay I can help you with your math!!
(-2,5)(9,-6)
slope(m) = (-6-5) / (9 - (-2) = -11/11 = -1
y = mx + b
slope(m) = -1
(-2,5)...x = -2 and y = 5
now we sub and solve for b, the y int
5 = -1(-2) + b
5 = 2 + b
5 - 2 = b
3 = b
so ur equation in slope intercept form is : y = -x + 3
The given terms are two terms apart, so their difference is twice the difference of adjacent terms.

The value of d is 4.
So to get the fractions easier to understand you need to put them on the same level you are on. So change the 9/10 gallons to 18/20 ( this makes them easier to deal with the 1/20)
so put 1/20 into 18/20. Liam can paint 18 bird houses.