21 of your taking about area
Answer:
110 db
Step-by-step explanation:
Consider a right triangle in which one of the angles
satisfies

That is, the side opposite
occurs in a ratio of 3 to 5 with the hypotenuse. The side adjacent to
then occurs in a ratio of 4 to 5 with the hypotenuse. In other words,

because

Then in this triangle,

Answer:
{-12,0}
Step-by-step explanation:
first to solve this can collect like terms and add
X² +12x=0
and solve it by factorization method
X² +12x=0
x(x+12)=0
it means x multiplied by x = X² then x multiplied by 12 = 12x
so this means x or (x+12) equals to zero
x=0 and (x+12)=0
x+12=0
x=-12
so the solution set is {-12,0}
but can also be done by formula method