Answer:
see explanation
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°, thus
∠1 = 180° - (72 + 57)° = 180° - 129° = 51°
The right angle at the left vertex is composed of 72° and ∠2, thus
∠2 = 90° - 72° = 18°
57° and ∠3 form a straight angle and are supplementary, thus
∠3 = 180° - 57° = 123°
∠4 = 180° - (∠2 + ∠3 ) ← sum of angles in a triangle
∠4 = 180° - (18 + 123)° = 180° - 141° = 39°
<span>its C. Alan has 13 CDs, Tom has 16 CDs, Barbara has 23 CDs !</span>
In mathematics, an inverse function (or anti-function) is a function that "reverses" another function: if the function f applied to an input x gives a result of y, then applying its inverse function g to y gives the result x, and vice versa, f(x) = y if and only if g(y) = x.
Answer:
-1
Step-by-step explanation: