Respuesta :

Hola User__________

Here is your Answer...!!!

____________________

Actually welcome to the concept of the Angle sum property...

The Angle sum property of a Quadilatetal =》

m/_A + m/_B + m/_C + m/_ D = 360°

Thus adding all the angles we get as....

=》 X + X + X+ 15° + X + 45° = 360°

=》 4X + 60° = 360°

thus ..4X = 360 - 60 = 300

Thus .. 4X = 300

X = 300 ÷ 4 =》 75°

X = 75°

Answer:   75

Step-by-step explanation:

The sum of the angles of a quadrilateral is 360°

(x) + (x) + (x + 15) + (x + 45) = 360

4x + 60 = 360

     - 60 - 60

4x         = 300

÷4             ÷4  

 x         =  75

Since the choices provided do not include 75, i worked each answer backwards to see if 15 degrees and/or 45 degrees was a typo:

A) 4(81) + y = 360    -->    y = 36

B) 4(61) + y = 360    -->    y = 116

C) 4(71) + y = 360    -->    y = 76

D) 4(51) + y = 360    -->    y = 156

Check to see if one of the x's had another number added to it.

A) if x - 24 is missing

B) if x + 56 is missing

C) if x + 16 is missing

D) if x + 96 is missing

My best guess is A or C