The ones with ✓ signs are irrational the rest are rational. note this is not generally true but it is for this particular set
Answer:
x = -5
y = 20
Step-by-step explanation:
3x + y = 5
3x - 3x + y = 5 - 3x
y = 5 - 3x
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4x + 2y = 20
4x + 2(5 - 3x) = 20
4x + 2(5) + 2(-3x) = 20
4x + 10 - 6x = 20
10 - 2x = 20
10 - 10 - 2x = 20 - 10
-2x = 10
-2x ÷ -2 = 10 ÷ -2
x = -5
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y = 5 - 3x
y = 5 - 3(-5)
y = 5 + 15
y = 20
Since we know that LCM of both 625&575 is 14375, we must find the hours it took for both planes to arrive at this same destination.
Plane 1(625): Took 23 hours to arrive.
Plane 2(575): Took 25 hours to arrive.
Therefore, the answer should be from 23-25 hours to arrive or if looking for middle number, 24 hours exactly.
Hope this helps.
