Speed = Distance / time.
Speed = 9000 meters / 12.12 seconds = 742.57 meters per second.
My "work" is to enter the equations into a graphing calculator and let it show me the answers--just as your "work" is to copy the question to Brainly.
The solutions are
(x, y) = (-0.5, 7.5)
(x, y) = (3, 25)
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When you equate the expressions for y, you get the quadratic
2x² -5x -3 = 0
(2x +1)(x -3) = 0
x = -1/2 or 3
y = 5(x +2) = 15/2 or 25
You asked what it is. It is a "one-step" linear equation in x.
The solution is found by multiplying both sides of the equation by -4. That gives you ...
... x = -100
All the primes of 24 is 1,2,3,4,6,8,12,and 24