Answer:
Step-by-step explanation:
This is a differential equation problem most easily solved with an exponential decay equation of the form
. We know that the initial amount of salt in the tank is 28 pounds, so
C = 28. Now we just need to find k.
The concentration of salt changes as the pure water flows in and the salt water flows out. So the change in concentration, where y is the concentration of salt in the tank, is 
. Thus, the change in the concentration of salt is found in
inflow of salt - outflow of salt
Pure water, what is flowing into the tank, has no salt in it at all; and since we don't know how much salt is leaving (our unknown, basically), the outflow at 3 gal/min is 3 times the amount of salt leaving out of the 400 gallons of salt water at time t:
Therefore,
or just
and in terms of time,
Thus, our equation is
and filling in 16 for the number of minutes in t:
y = 24.834 pounds of salt
The slope of a line perpendicular to another line has a
slope which is the negative reciprocal of that line or:
m1 = -1/m2
First, we convert the given equation into slope-intercept
form of a line: y = mx + b
8x + 15y = 12
15y = -8x + 12
y = (-8/15) x + 0.8
m1 = -8 / 15
Therefore the slope of the perpendicular line is:
m2 = 15 / 8
Since the perpendicular line crosses the point (11, 17), therefore
using the slope formula:
m = (y2 – y1) / (x2 – x1)
15 / 8 = (y2 – 17) / (x2 – 11)
1.875 (x2 – 11) = y2 – 17
1.875 x2 – 20.625 = y2 – 17
y2 = 1.875 x2 – 3.625
y = (15/8) x – 3.625
multiplying both sides by 8:
8y = 15x – 29
rewriting in standard form:
<span>15x – 8y = 29 (ANSWER)</span>
Answer:
You would need 2 1/2 gallons of paint to finish the room.
Step-by-step explanation:
Step 1: 12 x 8.5
Step 2: you should get 102. Then multiply 102 x 4
Step 3: then divide by 150 (which is the quotent of 75 x 2)
Your finally should be 2.72 :)
If the total amount of points in a test is 140, and we want to find 10% of those points, we can do the following to figure out how much points the question is worth...
140 points x 10% = 140 x 0.1 = 14 points for the short-answer quesion.
1) slope is 6 and y-intercept is ( 0,5) y = mx + b, m = 6, b = 5 y = 6x + 5 2)line passes through the points ( 3,6) and ( 6,3 ) First find the slope: m = (3-6)/(6-3) = -3/3 = -1 y = -x + b Plug in one of the given points (x,y) and find b 6 = -3 + b 9 = b <span> y = -x + 9</span> a horizontal line that passes through the point ( -1,7)Horizontal lines have a constant y-value and formaty = c where c is a constant number. y = 7 y=-3x+3x intercept: set y = 0 and solve for x0 = -3x + 33x = 3x = 1x-intercept: (1, 0) y-intercept: set x = 0 and solve for yy = -3(0) + 3y = 3y-intercept: (0,3) y=0,5x-1Is this two equations? The line y=0 has y-intercept at (0,0)The x-intercept is the entire x-axis y=5x-1x -intercept: Set y = 0 and solve for x y-intercept: Set x = 0 and solve for y
