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Ok Tomorrow I have a test in my physic's class and my teacher was nice enough to give us a study guide with the answers, but I can't figure out for my life how to get a few of the answers. I have 3 problems that I am having trouble with.

1. One force of 60N and a second of 30N act on an object at Point P. Graphically add the vectors and find the magnitude of the resultant when the angle between them is as follows:

a. 0

b. 30

c. 45

d. 60

Her answers: a. 90N (I got that one)

b. 87N

c. 84N

d. 79N

2. A person weighs 612N. If the person sits in the middle of a hammock that is 3.0m long and sags 1.0m below the points of support, what force would be exerted by each of the two hammock ropes?

Her answer: 457.3N

I will put the 3rd on in a little bit, just because their is a diagram that goes with it. Though I really need help with the 1st 2 b/c I just don't get one part of the 3rd question. Thanks!

Edit: since I was informed that I needed to show the troubles I having with the problems here they are:

I know in part a I just have to add the two vectors together. Then in Parts b-d I thought I was suppose to break up the vectors to have right triangles then use trig functions then Pythagorean's theorem to solve the equation.... but when ever I do that I keep on getting answers that are like 10N off. I am not sure if I am doing right. Can someone explain the steps I need to take into solving the equation.

For problem 2 ... I was wondering if someone can explain how to set up the diagram.

1. One force of 60N and a second of 30N act on an object at Point P. Graphically add the vectors and find the magnitude of the resultant when the angle between them is as follows:

a. 0

b. 30

c. 45

d. 60

Her answers: a. 90N (I got that one)

b. 87N

c. 84N

d. 79N

2. A person weighs 612N. If the person sits in the middle of a hammock that is 3.0m long and sags 1.0m below the points of support, what force would be exerted by each of the two hammock ropes?

Her answer: 457.3N

I will put the 3rd on in a little bit, just because their is a diagram that goes with it. Though I really need help with the 1st 2 b/c I just don't get one part of the 3rd question. Thanks!

Edit: since I was informed that I needed to show the troubles I having with the problems here they are:

I know in part a I just have to add the two vectors together. Then in Parts b-d I thought I was suppose to break up the vectors to have right triangles then use trig functions then Pythagorean's theorem to solve the equation.... but when ever I do that I keep on getting answers that are like 10N off. I am not sure if I am doing right. Can someone explain the steps I need to take into solving the equation.

For problem 2 ... I was wondering if someone can explain how to set up the diagram.

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