R = speed in still water
r + c = speed with current
r - c = speed against current
3.5(r + c) = 70
r + c = 20
c = 20 - r
4(r + c) = distance from pier to pier
5(r - c) = distance from pier to pier
4(r + c) = 5(r - c)
4(r + 20 - r) = 5(r - 20 + r)
80 = 10r - 100
180 = 10r
18 = r
The speed in still water is 18 km/hour
<u>Question 6</u>
1) 
, 
, O is the midpoint of 
, 
(given)
2) 
are right angles (perpendicular lines form right angles)
3) 
are right triangles (a triangle with a right angle is a right triangle)
4) 
(a midpoint splits a segment into two congruent parts)
5) 
(LL)
<u>Question 7</u>
1) 
are right angles), 
2) 
(reflexive property)
3) 
are right triangles (a triangle with a right angle is a right triangle)
4) 
(LL)
5) 
(CPCTC)
<u>Question 8</u>
1) 
, point D bisects 
(given)
2) 
are right angles (perpendicular lines form right angles)
3) are right triangles (a triangle with a right angle is a right triangle)
4) 
(definition of a bisector)
5) (reflexive property)
6) (LL)
7) 
(CPCTC)
Answer part A:
-6°F
Answer part B:
-7,5°F
Step-by-step explanation:
- A: 7-13= -6
- B: 11-5= 6 ==> 6*(-1,25)= - 7,5
Answer:
sir the picture is black
Step-by-step explanation:
