The least common multiple of 18, 20, and 24 is 360.
About 4.1 seconds. How long was the ball in the air? We are told that t represents time in seconds since the ball was thrown, so it started to be 'in the air' at t = 0 To answer the question, then, we need to know the time when it stopped being in the air. We are told that the ball hit the ground. So that's what happened when it stopped being airborne. We need to relate that event to the mathematics we're working with. What can we say about h , the height of the ball when the ball hits the ground? Answer: The height will be 0 when the ball stops being in the air. Now translate this back to the mathematics: The ball is in the air from t = 0 until the time t when h = 0 . Find the time t that makes h = 0 . That means: solve: − 5 t 2 + 20 t + 2 = 0 We can solve this by solving: 5 t 2 − 20 t − 2 = 0 (Either multiply both sides of the equation by − 1 , or add 5 x 2 − 20 x and − 2 to both sides and then re-write it the other way around) That's a quadratic equation, so try to factor first. But don't spend too much time trying to factor, because not every quadratic is easily factorable and that's OK, because we still have the quadratic formula if we need it. We do need it. t = − ( − 20 ) ± √ ( − 20 ) 2 − 4 ( 5 ) ( − 2 ) 2 ( 5 ) = 20 ± √ 440 10 = 20 ± √ 4 ( 110 ) 10 = 20 ± 2 √ 110 10 = 2 ( 10 ± √ 110 ) 2 ( 5 ) = 10 ± √ 110 5 We can see that 10 < √ 110 < 11 . In fact ( 10 + 1 2 ) 2 = 10 2 + 10 + 1 4 = 110.25 Using 10.25 as an approximation for √ 110 , we get : for the solution t = 10 − √ 110 5 we'll get a negative t . That doesn't make sense. The other solution gives t ≈ 10 + 10.25 5 = 20.5 5 = 4.1 seconds. So the ball was in the air from t = 0 until about t = 4.1 . The elapsed time is the difference, 4.1 seconds.
Given:
The width of a kitchen is 4.2 metres.
Kitchen cupboard widths are 60 cm.
To find:
The number of kitchen cupboard that will fit in 4.2 metres.
Solution:
Let x be the number of kitchen cupboard that will fit in 4.2 metres.
Width of 1 cupboard = 60 cm
Width of x cupboards = 60x cm
We know that, 1 m = 100 cm.
Width of a kitchen = 4.2 metres
= 4.2×100 cm
= 420 cm
Now, the width of the x cupboards is equal to width of the kitchen.



Therefore, the number of kitchen cupboard that will fit in 4.2 metres is 7.
Answer:
The answer is C and D.
Step-by-step explanation:
(-4)^1/2 = undefined
(-16)^1/4 = undefined
(-32)^1/5 = -2
(-8)^1/3 = -2
Answer:
Additive inverse of (5-6) is (6-5),
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So:
(5-6)+(6-5)=0
5-6+6-5=0
5-6=-6+5
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Left <--- -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6 ---> Right
Move 5 places to the right of -6 and you should land on -1.