Answer:
11.577 = r
Step-by-step explanation:
Comment
When you draw a sketch of this, <R is between p and q - - both of which are lines. The Cos law is the one you use.
Equation
r^2 = p^2 + q^2 - 2pq * Cos(R)
Givens
p = 21
q = 21
R = 32
r = ?
Solution
r^2 = 21^2 + 21^1 - 2*21*21 * Cos(32) Substitute givens into the equation
r^2 = 441 +441 - 882 * 0.8480 Add the first two terms.
r^2 = 882 - 747.98 Multiply Cos(32) by 2 * 21 * 21
r^2 = 134.02 Subtract 747.98 from 882
sqrt(r^2) = sqrt(134.02) Take the square root of both sides.
r = 11.577
