An electric motor pumps water into a pool at a rate of 500 liters per hour. After a tune up, its rate increases by x liters per hour. If the motor now takes 3 hours 19 pump
1800 liters, in which equation does x represent the increase in speed after the tune
up?
A, 500(2+3) 1800
B, 3(500) +2 1800
C. 5002 +3 1800
D, 3(500 + 2) 1800

b

step-by-step explanation:

the equation of a line in point- slope form is

y - b = m(x - a)

where m is the slope and (a, b) a point on the line

calculate m using the slope formula

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (0, 4) and (x₂, y₂ ) = (3, - 5) ← 2 points on the line

m = = = - 3

with m = - 3 and (a, b) = (3, - 5), then

y - (- 5) = - 3(x - 3), that is

y + 5 = - 3(x - 3) → b