(2,28),(5,7) slope = (7 - 28) / (5 - 2) = - 21/3 = -7...so it is draining at a rate of 7 gallons per minute
y = mx + b slope(m) = -7 (2,28)...x = 2 and y = 28 now we sub and find b, the y int 28 = -7(2) + b 28 = -14 + b 28 + 14 = b 42 = b so ur equation is : y = -7x + 42.....this is basically saying that when full, the bathtub holds 42 gallons and is draining at a rate of 7 gallons per minute
The slope-intercept formula is:y = m x + b,or: y = b - m x, since the rate is negative.For the 1st formula we have: y = 30 and x = 2For the 2nd formula: y = 12 and x = 5 ( because: 5 = 2 + 3, or : 3 minutes later, which can be confusing )30 = b - 2 m12 = b - 5 m--------------------b = 30 + 2 m12 = 30 + 2 m - 5 m3 m = 18m = 18 : 3 = 6b = 30 + 2 * 6 = 30 + 12 = 42Answer:y = 42 - 6 x
If you put it like 15/9 = 20/x, then cross multiply and divide you do 9 times 20 you get 180, then you divide 180 by 15 and you get 12. Hope this helps!
