Answer:
Hope this helps. Let me know if it doesn't and I'll try to help out. :)
Answer: 56 inches
Step-by-step explanation:
a. 60+58+64+72=254 (Add the average of his family without including him)
a. 62x5=310 (The average times 5, cause there are 5 of them will get you the total number of inches)
b. 310-254=56 (Subtract the total number of the 5 of them with the 4 of them to find Bill's height)
you can check your answer by adding all their heights.
You can group first two conjunctions and second two:

.
In first brackets you have common

and in second brackets common is 5:

.
Trig ratios can only be used on right triangles with acute measures.
If given an angle and there are adjacent and opposite sides, then use tan(opposite/adjacent)
If given an angle and there is an adjacent side and a hypotenuse, then use cosine(adjacent/hypotenuse)
If given an angle and there is an opposite and adjacent side, then use sin(opposite/hypotenuse)
A common mnemonic device used to memorize the trig rules is SOH-CAH-TOA