Mariah’s room has a length of 12 feet, a width of 11.5 feet. she knows that she is covering 423 ft2. what is the height of mariah’s room?

The height of the Mariah's room is 3.12 feet  

Step-by-step explanation:

Given as :

The length of the room = L = 12 feet

The breadth of the room = 11.5 feet

Let The height of room = H feet

The total surface area of room including ceiling and floor = 423 feet²

∵ The total surface area of room including ceiling and floor = 2 × ( Length × Breadth + Length × Height + Width × Height )

So, 2 × ( L × B + L × H + W × H ) = 423

Or, ( 12 × 11.5 + 12 × H + 11.5 × H ) =

Or, ( 12 × 11.5 + 12 × H + 11.5 × H ) = 211.5

Or, ( 12 × H + 11.5 × H ) = 211.5 - 138

Or, H × (12 + 11.5 ) = 73.5

Or,  H × 23.5 = 73.5

∴   H =

i.e H = 3.12 feet

So, The height of room = H =3.12 feet

Hence, The height of the Mariah's room is 3.12 feet  Answer

∠acb = 8°

step-by-step explanation:

∠xba lies on the circle and is half the measure of the intercepted arc ax

hence

measure of arc ax = 2 × 42° = 84°

∠acb is outside the circle and is

∠acb = (arcab - arcax ), hence

∠acb = 0.5 (100 - 84) = 0.5 × 16° = 8°

definition: a circle is the  set of all points in a plane that are equidistant  from a given  point  called the center of the circle. we use the symbol ⊙ to represent a circle. the a line segment from the center of the circle to  any point  on the circle is a radius of the circle.

step-by-step explanation:

i googled it and this is what i got i don't know how it is. sorry.