Abcd is a square, what is the measure angle of bac

45 degrees, you are cutting the right angle in half

measure of ∠BAC  is  45°

Step-by-step explanation:

We have Square ABCD

we need to find the measure of ∠BAC

Let us take ΔBAC

We know that all the angles in a square is equal to  90°

Therefore ΔBAC is right angled triangle since  ∠ABC= 90°

Sum of angles in a triangle = 180°

∠ABC + ∠BCA + ∠BAC = 180°

90° + ∠BCA + ∠BAC =180°  ( since  ∠ABC= 90°)

∠BCA + ∠BAC =180° -90°  ( subtracting 90° from both sides)

∠BCA + ∠BAC = 90°

sides of square are equal so  AB = BC  and angles opposite to equal sides are equal hence ∠BCA = ∠BAC

so we have

∠BAC+∠BAC = 90°  

2∠BAC = 90°  

∠BAC = 45°   ( divide both sides by 2)

so we have measure of ∠BAC  is  45°  

17 is c. congruent means equal in size

No a triangle cannot be formed because when you add the two smallest number together (which would be 11) the have to be bigger than the number it is "against" ( which would be 12)