Step-by-step explanation:
it is an isoceles triangle (equally long legs).
there is a right angle at W, so YW is the height of the isoceles triangle XYZ.
that means W splits XZ in half.
therefore,
ZW = XZ/2 = 38/2 = 19
Answer: number one is d and number 3 is c I think
Step-by-step explanation:
Permutation: In a race of 10 students, find the number of ways students can finish 1st, 2nd, and 3rd. In this case the order matters, so it is a permutation.
10 x 9 x 8 = 720 ways
Combination: In a class of 10 students, find the number of ways a group of 3 students can be selected to win a prize. In this case the order doesn't matter, so it's a combination.
10 x 9 x 8 / (3 x 2 x 1) = 120 ways