What is the value of x? The image is of a triangle with a base marked as 21. The other two sides are 10 and 17. Altitude from the top vertex to the base is marked as ALTCxALTC.

A. 6
B. 7
C. 8
D. 9

Plzzzzzzzzzzzzzzzzzzzzzzzzz will give brainliest

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?

Satchi found a used bookstore that sells pre-owned dvds and cds. dvds cost $9 each, and cds cost $7 each. satchi can spend no more than $45.