A) Divide total miles by total time:
21 miles / 4 hours = 5.25 miles per hour.
B) Divide miles by miles per hour:
42 miles / 5.25 miles per hour = 8 hours.
Answer:

Step-by-step explanation:
The function is given.

To find : 
The input for the function f(x) is (a + 1).
Replace x with (a + 1).

Expand brackets.

Simplifying.

Given :-
- a² - 2a - b² = 0
- 2b + 2ab = 0
To find :-
Solution :-
<u>Taking</u><u> </u><u>second</u><u> </u><u>equation</u><u>:</u><u>-</u>
- 2b + 2ab = 0
- 2b ( 1 + a ) = 0
- 2b = 0 or (1+a) = 0
- b = 0 , a = -1
<u>Substitute</u><u> </u><u>in </u><u>first </u><u>equation</u><u> </u><u>:</u><u>-</u><u> </u>
<u>When </u><u>b </u><u>=</u><u> </u><u>0</u><u> </u><u>,</u>
- a² - 2a - 0² = 0
- a² - a = 0
- a( a -1) =0
- a = 0 , 1
<u>When </u><u>a </u><u>=</u><u> </u><u>-</u><u>1</u><u> </u><u>,</u>
- (-1)² - 2*(-1) - b² = 0
- 1 + 2 - b² = 0
- b² = 3
- b = ±√3
<u>Answer </u><u>:</u><u>-</u><u> </u>
- a = 0,1 ; b = 0
- a = -1 , b = ±√3
Answer:
4 by 2
Step-by-step explanation:
you can basically guess and check with this question but I knew if it was a rectangle then 2 sides would be larger than the other. So I started off figuring out what times what equals 8 and I got 2 and 4. So I put those in for the side lengths and I got 12.
Answer:
P = 4x + 10
Step-by-step explanation:
perimeter of a rectangle = 2( width + length )
P = 2 ( x - 2 + x + 7 )
P = 2 ( x + x + 7 - 2 )
P = 2 ( 2x + 5 )
P = 4x + 10