Step 1: Read and understand the problem statement.
You are given (time, depth) pairs of (20 s, 8 cm) and (40 s, 0 cm) and asked to write an equation that describes the relationship of depth (y) to time (x).
The rate of change is (0 cm -8 cm)/(40 s -20 s) = -8 cm/(20 s) = -2/5 cm/s. Then in point-slope form using the second point, the linear function rule is
y = (-2/5)(x -40) +0
You can expand this to
y = (-2/5)x +16
y = -0.4x +16 . . . . . . using a decimal number for the slope
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If the bathtubs in your "draining race" start with the same level, the one with the steepest slope (-0.5 cm/s) will win.
Answer:
(2,10) or x=2 y=10
Step-by-step explanation:
<em>1. Pick one of your equations and solve for a variable. I chose the first equation and solved for x.</em>
5x-2y=-10 (Move the -2y to the other side, you need to do the opposite so you add +2y to -10)
5x=2y-10 (Divide the 5 from the x)
x=2/5y-2
<em>2. Now take what you got for x and plug it into the x variable on the other equation.</em>
3(2/5y-2)+6y=66 (Multiply 3 by 2/5y and -2)
6/5y-6=6y=66 (Move the -6 to the other side and add 6/5y to 6y)
36/5y=72 (Since the number on the y is a fraction, you must do the opposite to the other side)
y=72/1 x 5/36 (Flip your fraction and multiply it by the 72)
y=10
<em>3. Now that you have one of the variables solved for, in order to get the other we must plug in what we have to the first equation.</em>
5x-2(10)=-10 (Multiple 2 by 10)
5x-20=-10 (Move -20 to the other side, since you do the opposite add +20 to the -10)
5x=10 ( Divide 10 by 5)
x= 2
<em>4. If needed, plug in the values of x and y to check your solution.</em>
Hope this could help! :)
Answer:
Yes
Step-by-step explanation:
No. Because a irrational number has a repeating pattern.