# Example 7.1
MKS(kN)
ay = 16 kN - 12 kN + 4 kN

# Example 7.2
MKS(N, N m)
Td = -10 N m + 15 N m + 20 N m
Tb = -10 N m + 15 N m
Tc = 25 N m

# Example 7.3
MKS(kN, kN m)
ay = (9 kN m + 6 kN * 6 m) / 9 m
vb = 5 kN
mb = 5 kN * 3 m
vc = 6 kN - 5 kN
mc = 5 kN * 3 m

# Example 7.4
FPS(lb ft)
fdc = 400 lb * 4 ft / ((3/5) * 8 ft)
ax = (4/5) * fdc
ay = 400 lb - (3/5) * fdc
nb = 266.7 lb
vb = 0
mb = 200 lb * 4 ft - 200 lb * 2 ft

# Example 7.5
MKS(N, N m, deg)
q = 45 deg
r = 600 N / sin(q)
ve = r * cos(q)
ne = -r * sin(q)
me = r * cos(q) * 0.5 m

# Example 7.6
MKS(kN, kN m, deg)
w = [0, 0, 6375 ] N
fa = [-13.5, 0, 0] kN
r = [0, 3, 5.25] m
ma = -cross(r, (fa + w))
mag(ma)

# Example 7.13
MKS(kN, kN m, deg)
ay = ((4 kN) * (15 m) + (15 kN) * (10 m) + (3 kN) * (2 m)) / (18 m)
ey = -(12 - 4 - 15 - 3) kN
ax = (12 kN * 8 m - 4 kN * 5 m) / 12 m
ex = ax
BEGIN
  tbc = 1 N
  q = 45 deg
  fx = tbc * cos(q) - 6.33 kN
  fy = 12 kN - 4 kN - tbc * sin(q)
END
solve(fx,fy,tbc,q)
BEGIN
  tab = 1 N
  q = 1 deg
  fx = tab * cos(q) - 6.33 kN
  fy = -tab * sin(q) + 12 kN
END
solve(fx,fy,tab,q)
BEGIN
   tcd = 1 N
   q = 1 deg
   fx = tcd * cos(q) - 10.2 kN * cos(51.6 deg)
   fy = tcd * sin(q) + 10.2 kN * sin(51.6 deg) - 15 kN
END
solve(fx,fy,tcd,q)
BEGIN
   ted = 1 N
   q = 1 deg
   fx = 6.33 kN - ted * cos(q)
   fy = 10 kN - ted * sin(q)
END
solve(fx,fy,ted,q)

# Example 7.15
MKS(kN, kN m, deg)
y = 9.19 * (cosh(0.109 * 10) - 1) m
LL = 2* (45.9 N) / (5 N/m) * sinh(5 * 10 / 45.9)
q = atan(5 * 12.1 / 45.9)
tmax = 45.9 N / cos(q)

# Homework Problems:

TBD