See how many times the denominator goes into the numerator. For example, with 24/8, 8 goes into 24 three times, so 24/8 is 3. If I had 25/8, then it would be 3 1/8 because you have one left over after you divide the 8 into 25.
Answer: Yes, y does vary directly with x.
Constant of variation = 1/4
The function rule is y = (1/4)x
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Explanation:
Let's assume that y does vary directly with x.
If that's the case, then we have an equation in the form y = kx, where k is the constant of variation.
Solving for k gets us k = y/x
For each row, divide the y value over the x value
- row one: k = y/x = 14/56 = 0.25
- row two: k = y/x = 20/80 = 0.25
- row three: k = y/x = 22/88 = 0.25
Each row yields the value k = 0.25 and it fully confirms y does vary directly with x.
So y = kx becomes y = 0.25x as the function rule, which is equivalent to y = (1/4)x
Answer:
f = 1, w = 4
Step-by-step explanation:
Given the 2 equations
5w = 23 - 3f → (1)
4f = 12 - 2w (add 2w to both sides )
2w + 4f = 12 ( subtract 4f from both sides )
2w = 12 - 4f → (2)
Multiplying (1) by 4 and (2) by - 3 and adding the result will eliminate f
20w = 92 - 12f → (3)
- 6w = - 36 + 12f → (4)
Add (3) and (4) term by term to eliminate f
14w = 56 ( divide both sides by 14 )
w = 4
Substitute w = 4 into either of the 2 equations and solve for f
Substituting into (1)
5(4) = 23 - 3f
20 = 23 - 3f ( subtract 23 from both sides )
- 3 = 3f ( divide both sides by - 3 )
1 = f
Let the speed for the first 12 mi be x mi/h, the speed for 18 mi was (x+4) mi/h
thus given that
time=distance/speed
the average time will be:
3=(12+18)/(x+x+4)
3=30/(2x+4)
solving for x we get
3(2x+4)=30
6x+6=30
6x=24
x=4 mi/hr
Answer: 12 mi/hr
F(3) = 16, you simply plug in 3 for x to find the answer.
