So x + y = 45, and 4x + 5y = 195. Get y by itself. Subtract x from both sides in the first equation to get y = 45 -x, and subtract 4x from the second equation to get 5y = 195 - 4x. Divide by 5 to both sides to get y = 39 - 4/5x. 39 - 4/5x = 45 - x. Add x to both sides to get 39 - 1/5x = 45. Subtract 39 from both sides to get -1/5x = 6. Divide by -1/5 to get x = -30, or 30. In the first equation, do 30 + y = 45. Subtract 30 from both sides to get y = 15. Check. 4(30) + 15(5) = 195, or 120 + 75 = 195.
Answer:
um....
1. 4
2. 3
3. 5
4. 8
Hope this helps.
Step-by-step explanation:
Answer:
m = 35
Step-by-step explanation:
2m + m -15 = 90
3m -15 = 90
+15 +15
3m = 105
/3 /3
m = 35
To check the work just insert 35 for m:
2(35) + 35 -15 = 90
70 + 35 -15 = 90
105 - 15 = 90
90 = 90
Answer:
This is an "Experiment" type of study
Step-by-step explanation:
Researchers use various methods or techniques to conduct research and draw conclusions from it. Some of these methods are given below
1. Experiment
2. Observational study
3. Anecdotal evidence
1. Experiment: In this type of study, researchers have control over their setup and they can give directions or apply any treatment on their subjects.
2. Observational study: In this type of study, researchers cannot give directions or apply any treatment on their subjects but rather they can only observe what is going on.
3. Anecdotal evidence: Also refers to experience and can be defined as personal experience based on something.
The study that we are given is clearly an example of "experiment" since half of the participants were to told walk 2 miles a day for 6 weeks. The researchers have control over their subjects in this case and they gave directions to their subjects to do this and that.
This could have been an observational study if researchers had selected 10 people who walked 2 miles a day for 6 weeks and 10 people who did not walk 2 miles a day for 6 weeks and simply measured their blood pressure and come to a conclusion. This way, it would have been a case of observational study.
