Answer:
y =
x²
Step-by-step explanation:
Given that y and x² are directly proportional then the equation relating them is
y = kx² ← k is the constant of proportion
When x = 2
y = k × 2² = 4k
When x = 5
y = k × 5² = 25k
Then
25k - 4k = 20 ( difference between values is 20 )
21k = 20 ( divide both sides by 21 )
k = 
y =
x² ← equation of proportion
Answer: 48 model cars
Step-by-step explanation: 1. You know that the ratio of the number of model cars that Jim owns to the number of model cars Terrence owns is 4:3.
2. Let's call the number of model cars that Jim owns is , therefore, you can solve the exercise as following:
3. Therefore, Jims owns 48 model cars.
See this solution/explanation (answer is '7 meters'):
1. According to the condition 'y' means the height, and 'x' - the length from the start of the lift hill.
2. The phrase 'height of 343 meters' means y=343.
3. From the another side y=x³. If to substitute 343 instead of 'y': 343=x³, - it is possible to find the value of 'x'.
x=<u>7 [m]</u> - how far from the start of the lift hill...
Y= -4/5x -1.5
I believe this right!