My father taught me a method that I call, 'throwing some thing over the wall'. There is a sample equation for the first picture that shows you how it works. It's a great way to help isolate the variable and I hope that it works for you. The second picture contains the answers I got through the use of this method. I'm sorry for the messy handwriting; I was on a bus.
If Melanie get's 4.10$, then Jacob get's 20.50$.
We can divide to get the unit rate:
20.50 ÷ 4.10 = 5
This means that if Jacob gets 5$, then Melanie will get 1$.
So in this case, Melanie get's 1$.
Answer:
B
Step-by-step explanation:
Answer:
(a) 
(b) 
Step-by-step explanation:
Given
Variation: Inverse proportional.
This is represented as:
See attachment for table
Solving (a):
First convert variation to equation
From the table:
So, we have:
Substitute 4 for k in
Solving (b): x when y = 25.
Substitute 25 for y in
Cross Multiply
Divide through by 25
Take positive square roots of both sides
Solve for x:
(-4 x - 2) (x - 7) = 0
Split into two equations:
-4 x - 2 = 0 or x - 7 = 0
Factor constant terms from the left hand side:
-2 (2 x + 1) = 0 or x - 7 = 0
Divide both sides by -2:
2 x + 1 = 0 or x - 7 = 0
Subtract 1 from both sides:
2 x = -1 or x - 7 = 0
Divide both sides by 2:
x = -1/2 or x - 7 = 0
Add 7 to both sides:
Answer: x = -1/2 or x = 7
