If you want to turn a fraction to a decimal, you have to divide the numerator by the denominator in order to get a decimal number. If the fraction is a mixed number, you would do the same but make sure that the whole number is in front of the decimal.
The answer to -15.375÷0 would be neither. This is because you can't divide any number by zero. Any number tried to be divided by zero would be undefined.
Answer:
a = 9.849
b = 20.25
c = 491.03
Step-by-step explanation:
By using Pythagoras theorem in the right triangle BDC,
(Hypotenuse)² = (Leg 1)² + (Leg 2)²
BC² = BD² + DC²
a² = 9² + 4²
a = 
a = 
a = 9.8489
a ≈ 9.849 units
By mean proportional theorem,

AD × DC = BD²
b × 4 = 9²
b = 
b = 20.25 units
BY Pythagoras theorem in ΔADB,
AB² = AD² + BD²
c² = b² + 9²
c² = (20.25)² + 9²
c² = 410.0625 + 81
c = 491.0625
c = 491. 063 units
X=80°
A triangle’s angle measurements always add up to 180°. So 180-70-30=80