I can't figure this out for the life of me.(adsbygoogle = window.adsbygoogle || []).push({});

Vector A = 7.00 m and points 40.0o north of east. Vector B = 3.00 m and points 20.0o west of north, and Vector C = 3.00 m and points 35.0o west of south.

What is the magnitude of the resultant vector A+B+C?

What angle does the resultant vector A+B+C make with respect to the east?

So I've drawn it out and everything and I'm solving for "D" and what I drew out was some weird quadralateral(sp?). Anyways I solved for each of the Vectors and got the X Components and the Y Components. And this is what I got.

A -> Ax = (7.0m)(sin(40 deg)) = 4.5m

Ay = (7.0m)(cos(40 deg)) = 5.4m

B -> Bx = (3.0m)(cos(20 deg)) = 2.8m

By = (3.0m)(sin(20 deg)) = 1.0m

C -> Cx = (3.0m)(sin(35 deg)) = 1.7m

Cy = (3.0m)(cos(35deg)) = 2.5m

So then I added all the x components and all the y components and got the x and y components for D.

Dx = 4.5m - 2.8m + 1.7m = 3.4 m

Dy = 5.4m + 1.0m + 2.5m = 8.9m

and then I used the pythagorean theorem to get D which would be

3.4^2 + 8.9^2 = D^2

D = 9.5m

and I thought that was my answer but its telling me it was wrong. So I didn't even attempt to get the angle because that will probably be wrong to.

So yeah can someone help me please

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# Homework Help: Help Please! Vector Problem.

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