I think its C but not sure
Angle 1 = 30°
Angle 2 = 90°
⇒ Angle 3 = 60°
So, it's right triangle. We can set the length of one side and get all other sides.
So, we have 1 triangle. If there are 2 or more triangles with the same data, all the triangles will be congruent because of : <span>Two triangles are </span><span>congruent if </span>"<span>ASA: Two interior angles and the included side in a triangle have the same measure and length, respectively, as those in the other triangle</span><span>.</span>"
81 is 45% of 180.
Simply multiply the percentage rate to the whole to get the part it is representing.
180 is the whole or 100%
45% is the percentage rate of the part.
180 x 45% = 81
81 is the value of the part
Assuming the part and the whole is given, to get the percentage rate, simply divide the part by the whole. and multiply its quotient by 100%.
81/180 = 0.45 x 100% = 45%
In the instance that the part and its corresponding percentage rate is given, find the whole. divide the part by its percentage rate.
81/45% or 81/0.45 = 180