Three astronauts equipped with jetpacks

[p14r]

Three astronauts equipped with jetpacks are pushing a satellite, having a mass of 121kg, through space. The forces being exerted on the satellite are F1=31.8N at an angle of 31.0 degrees above the horizontal (θ1), F2=40.0N at 60.2 degrees below the horizontal (θ2), and F3=54.7N along the horizontal.

What is the magnitude of the satellite's acceleration?

So I tried to solve it by adding all the FnetX, and Fnet Y

Fnet x= 31.8 cos 31 + 54.7 + 40.0 cos 60.2
= 27.2579 + 54.7 + 19.8789584
= 101.8368786 N

Fnet y= 31.8 sin 31 - 40.0 sin 60.2
= 16.37821 - 34.71061813
= -18.332408 N

tan θ = 101.8368786 / -18.332408
θ = -79.79506177

sin θ = Fnet x/ Fnet
sin (-79.79506177) = 101.8368786/ Fnet
Fnet = -103.47 N

Fnet = ma
a = Fnet/m
a = -103.4737987 N/121 kg
a = -0.85 m/s^2

But apparently it's wrong, can someone help please?

 

[Doc Al]

Fnet = ma
a = Fnet/m
a = -103.4737987 N/121 kg
a = -0.85 m/s^2

But apparently it's wrong, can someone help please?

Did you include the minus sign in your answer? They wanted the magnitude of the acceleration.

 

[p14r]

Yup i did, so i shouldn't enter the negative sign?

 

[Doc Al]

Yup i did, so i shouldn't enter the negative sign?

No you shouldn't. Magnitudes are unsigned.

 

[p14r]

It worked, thank you so much!