Answer:
Step-by-step explanation:
50 X 4= 200
90 X 5=450
50 X 5=250
200 + 250 = 450
Therefore it takes 5 hours for train B which is the train moving at 90 km per hr to catch up to train A.
Answer:
8π
Step-by-step explanation:
360° = 2πr = πd
120° = 1/3 * 360°
120° = 2/3πr = 1/3πd
If the radius r = 12:
arcAB = 2/3π * 12 = 8π
Answer:
2 vertically and -11 horizontally
Explanation:
the graph shifts 2 vertically and -11 horizontally
note: vertically is up ↑ and bottom ↓ , horizontal is right → and left ←
20. (2) 14
A perfect square trinomial will factor into two expressions that are the same, for example: x^2 + 6x + 9 = (x + 3)(x + 3). Since this problem has a C value of 49, it will factor into (x + 7)(x + 7). 7 doubled is 14, therefore one possible value of B is 7.
21. (4) 2, -12
x^2 + 10x + 25 = 24 + 25
(x + 5)^2 = 49
x + 5 = +/- 7
x = 2, -12
22. (3) 3 + sqrt(17)
x^2 - 6x = 8
Complete the Square
x^2 - 6x + 9 = 8 + 9
(x - 3)^2 = 17
x - 3 = +/- sqrt(17)
x = 3 + sqrt(17), 3 - sqrt(17)
23. (1) 1, -5
x^2 + 4x - 5 = 0
x^2 + 4x = 5
x^2 + 4x + 4 = 5 + 4
(x + 2)^2 = 9
x + 2 = +/- 3
x = 1, -5
Hope this helps!