9x + 4 = 58
9x = 54
x = 6
The number is 6.
If the legs are length a and b and hyptonuse is c then
a²+b²=c²
so
if the legs are 20 and 21 and the hypotnuse is x then
20²+21²=x²
400+441=x²
841=x²
29=x
If the sum of their lengths is 5,520 miles then River D is 2360 and River C is 3160
Answer:5in
Step-by-step explanation:
1. Identify the triangle
you are given a right triangle with the hypotonus missing and are given the side lengths 3 and 4 you know the hypotonus is 5 by the 3,4,5 Pythagorean tripe, if you do not notice this it can be solved with the Pythagorean theorem a^2+b^2=c^2
2. solve (if not done with 3,4,5 triple)
3^2+4^2=c^2
9+16=c^2
25=c^2
5=c | square root both sides to cancel the square
Answer : a link for your answer<em> https://quizlet.com/140197143/surface-area-and-volume-surface-area-of-rectangular-pyramids-flash-cards/</em>
<em>Step-by-step explanation:</em>
