Remark
You are dealing with a right angle triangle. You can use one of Sin(x) Cos(x) or Tan(x). Since the Hypotenuse is involved and since you are given the adjacent side, Cos(71) is what you will need.
Solution
H = BC
Cos(x) = adjactent / hypotenuse
Cos(71) = 6.3 / H Multiply both sides by H
H * Cos(71) = 6.3 Divide by Cos(71)
H = 6.3 / cos(71) Cos(71) = 0.32557
H = 6.3 / 0.32557 Divide
H = BC = 19.351 Answer
11 1/2+6 4/5 equals? So, you have to make each fraction have the same denominator. So, you would notice that they have in LCD (least common denominator )which is 10. So you're new fractions are 11 5/10+ 6 8/10. 11+6=17. 5/10+8/20=13/10. Which simplified it would be 1 3/10. 17+1 3/10 equals 18 3/10. 18 3/10 -3 3/10 equals 15. 15 is the answer.
Recall the secant-tangent theorem, and you have
EA^2 = EC*CD
12^2 = 8*(x+10)
and now ED = EC+CD = 8+x+10
I suspect a typo somewhere in the murk above
We want to solve the equation :
first, multiply both sides by 4:
divide both sides by 3:
add -3 to both sides:
Answer: x=9
