Answer:
4. C. x = 4 or -4
Step-by-step explanation:
since both terms are perfect squares, factor using the difference of squares formula, a² - b² = ( a + b ) ( 
- b ) where
Let the boat speed in still water be b.
Let the current speed be c.
The speed going upstream is 20/4 = 5 mph.
The speed going downstream is 32/4 = 8 mph.
b - c = 5 ........(1)
b + c = 8 .......(2)
Adding equations (1) and (2) we get:
2b = 13
b = 13/2 = 6.5
Plugging in the value for b into equation (1) we find c = 1.5.
The boat speed in still water is 6.5 mph and the current speed is 1.5 mph.
Answer:
Face diagonal of a cube:
Step-by-step explanation:
f2 = a2 + a. Then f2 = 2a.
8x40=320 (+) 8x7=56 (=) 376.
A=40
hope this helped
