Answer: 90 Earth years.
Step-by-step explanation:
Analizing the information provided in the exercise, you need to find the Least Common Multiple (LCM) of the given numbers.
You can follow these steps:
1. You must descompose 6, 9, 15 and 18 into their prime factors:

2. Finally, you need to choose the commons and non commons with their greatest exponents and multiply them. Then you get:

Therefore, it will take 90 Earth years for them to all line up.
The answer is .5 :) because 3 is half of 6
5x-5=-7y
3x+2y=-8
First, you need to rearrange the first equation so it is in the same format as the second one.
5x-5=-7y
Add 5 to both sides
5x-5+5=-7y+5
Add 7y to both sides
5x+7y=-7y+7y+5
So you have 5x+7y=5
Now you need to multiply that equation by 3
3(5x+7y=5)
15x+21y=15
Multiply the second equation by -5
-5(3x+2y=-8)
-15x-10y=40
Now add them together
15x+21y=15
+(-15x-10y=40)
---------------------
11y=55
y=5
Now plug y=5 into one of the original equations and solve for x.
3x+2(5)=-8
3x+10=-8
3x=-8-10
3x=-18
x=-6
To check the solution plug them both into the other equation:
5(-6)-5=-7(5)
-30-5=-35
-35=-35
It checks.
Hope that helps.
Answer:
a) The number of correct answers
b) Discrete
c) Ratio
Step-by-step explanation:
We are given the following in the question:
Experiment:
Evaluate the effectiveness of different study strategies. All students were then given a test on the passage material and the researchers recorded the number of correct answers.
a) The dependent Variable
The number of correct answers given is the dependent variable because it depends on the number of times the passage is read.
b) Nature of dependent variable.
- It is a discrete variable.
- Since, the number of questions will always be expressed in whole numbers and cannot be expressed as decimals.
- They are always counted and not measured.
c) Scale of measurement
- Ratio is used to measure the dependent variable because true zero for the number of correct questions answered exist.
- If the measure is zero that means truly no questions were answered correctly.
Answer:
Step-by-step explanation:
we will multiply first
-4x+16=12
-4x=12-16
-4x=-4
x=1