xis less than or equal to -3
y-y1 = m(x-x1)
where: x1 = 1 y1 = 8 (given point (1,8) and m = -3
y - (8) = -3 (x - (1))
y - 8 = -3 (x-1)
y- 8 = -3x +1
When estimating, compatible numbers are numbers that are close in value to the actual numbers, and which make it easy to do mental arithmetic.
