The Muslim mathematicians adopted a numerical system from India. The correct answer is B.
Know that:
sin(β)=Opposite/Hypotenuse
Therefore:
sin(54)=x/10
Therefore:
x=10*sin(54)
x=8.1 (To the nearest tenth)
Use the Pythagorean Theorem.
a² + b² = c²
3² + b² = 19²
9 + b² = 361
b² = 352
b = 4√11
Now, solve for the remaining angles by using the trigonometric ratios:
Sine = opposite/hypotenuse
sin(A)= 3/19
sininverse(3/19) = 9.1 = angle A
180-9.1-90 = 80.9 = angle B
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