The formula you should use is Area = 1/2bh, in other words, area equals half times base times height. Now, substitute everything in, the equation should now be 221.16 = 1/2*b*29.1. This simplifies into 221.16 = 14.55b, now divide 14.55 on both sides, which leaves us to 15.2 = b. However, don't forget the units, which the answer (length of base) should be 15.2 in.^2.
The Triangle Sum Theorem states that the sum of the angles of a triangle equal 180°. Therefore, 45° + 62° + k = 180 107° + k = 180 k = 73° The value of k is 73°
