If x > 0 then |x|/x = 1 !!!
If x<0 then |x|/x = -1
*below is an explanation! :)
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- I found the answer to this by choosing a any number that satisfies the requirement of x > 0 and plugging it into |x|/x
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Watch this!
Let's take 10 for example. 10 is greater than 0 like x>0 requires!
Let's plug it into |x|/x
|10| ÷ 10 = 1
*Remember that | | this means "absolute value" or whatever is in between the two bars will always be positive (+)
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Now let's take a random number that satisfies 0> x and do the same as we did above!
Let's take -3 and plut it into |x|/x
|-3| ÷ -3 = -1
,,,,,??,??,,,,,,,,,,,,,,,,
Andre45 [30]
Answer:
the one real zero is in the interval (-1, 0)
Step-by-step explanation:
Descartes' rule of signs tells you there are 0 or 2 positive real zeros. Changing the signs of the odd-degree terms and applying that rule again tells you there is one negative real zero. At the same time, those coefficients (-3, -5, -5, +7) have a negative sum, so you know ...
f(-1) = -6
f(0) = +7
so there is a zero in the interval (-1, 0).
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You can try a few values between x=0 and x=10 to see what the function does in that part of the graph. You find ...
f(1) = 10
f(2) = 21
f(3) = 58
So, it is safe to conclude that there are no real zeros for x > 0.
The only real zero of f(x) is in the interval (-1, 0).
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I like to use a graphing calculator for problems like this.
The equation would be 4y=5x 4(x+15)=5x x+15=y
let x be the amount that Shelia deposits each time
let y represent the amount that Sherri deposits each time
4(x+15)=5x
4x+60=5x
-4x -4x
60=x
Check:
x+15=y 60+15=y y=75
4(75)=5(60)
300=300
Shelia deposits $60 each time.