Answer:
(3, 50) and (14,303)
Step-by-step explanation:
Given the system of equations;
y=23x–19 ....1
x²–y= – 6x–23 ...2
Substitute 1 into 2;
x²–(23x-19)= – 6x–23
x²–23x+19= – 6x–23 .
x²-23x + 6x + 19 + 23 = 0
x² - 17x + 42 = 0
Factorize;
x² - 14x - 3x + 42 = 0
x(x-14)-3(x-14) = 0
(x-3)(x-14) = 0
x = 3 and 14
If x = 3
y = 23(3) - 19
y = 69-19
y = 50
If x = 14
y = 23(14) - 19
y = 322-19
y = 303
Hence the coordinate solutions are (3, 50) and (14,303)
Let the slower runners speed be X kilometers per hour.
Then the faster runners speed would be X+2 kilometers per hour.
The formula for distance is Speed times time.
The distance is given as 30 kilometers and time is given as 3 hours.
Since there are two runners you need to add the both of them together.
The equation becomes 30 = 3x + 3(x+2)
Now solve for x:
30 = 3x + 3(x+2)
Simplify:
30 = 3x + 3x +6
30 = 6x + 6
Subtract 6 from each side:
24 = 6x
Divide both sides by 6:
x = 24/6
x = 4
The slower runner ran at 4 kilometers per hour.
The faster runner ran at 4+2 = 6 kilometers per hour.
Answer:
[7, -4, -8]
Step-by-step explanation:
Just simply plug in each choice into the equations to confirm their authenticities.