80*t+70*t=50
t = .33 hours =20 minutes
This assumes the trains are going opposite directions (opposite tracks so I’m assuming opposite directions)
Answer:
La edad actual de Beatriz es de:
30 años
Step-by-step explanation:
Planteamiento:
5e = 4b
(e+3) + (b+3) = 60
e = edad actual de José
b = edad actual de Beatriz
Desarrollo:
de la segunda ecuación del planteamiento:
e + b + 6 = 60
e + b = 60 - 6
e + b = 54
e = 54 - b
sustituyendo este último valor en la primer ecuación del planteamiento:
5(54-b) = 4b
5*54 + 5*-b = 4b
270 - 5b = 4b
270 = 4b + 5b
270 = 9b
b = 270/9
b = 30
e = 54 - b
e = 54 - 30
e = 24
Comprobación:
5e = 4b
5*24 = 4*30 = 120
Answer:
x + y = 50 (1) and 2x + 3y = 115 (2); x = 35, y = 15
Step-by-step explanation:
Since x represents the number of 2 point shots and y represents the number of 3 point shots. If the total number of shots is 50, then x + y = 50 (1)
Also, the total 2 point shots is number of 2 point shots × points per shot = 2x and the total 3 point shots is number of 3 point shots × points per shot = 3y. Since the total number of points is 115, then
2x + 3y = 115 (2)
So, the system of equations are
x + y = 50 (1) and 2x + 3y = 115 (2)
We can solve for x and y by substituting x = 50 - y into (2)
So, 2(50 - y) + 3y = 115
100 - 2y + 3y = 115
100 + y = 115
y = 115 - 100
y = 15
So, x = 50 - y
= 50 - 15
= 35
B is the answer
just like the picture
( T' is not exact. it just shows the reflection)
Answer:
Step-by-step explanation:
The least number of degree is 3 and the third root should be (4 - i) to make polynomial rational.
<u>The polynomial is:</u>
- (x - 3)(x - (4 + i))(x - (4 + i)) =
- (x - 3)(x² -x(4 + i + 4 - i) + (4 + i)(4 - i)) =
- (x - 3)(x² - 8x + 16 - (-1)) =
- (x - 3)(x² - 8x + 17) =
- x³ - 8x² + 17x - 3x² + 24x - 51 =
- x³ - 11x² + 41x - 51
