1 kilometer= 1000 meters
3x1000= 3000 meters
3000/ 25= 120 pool lengths
4 - 20% is equal to 3.2 (You could've used a calculator.
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Explanation:</h2><h2>
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Here we need to set a system of two linear equations in two variables. So:
- <em>The sum of digits in a two digit number formed by two digits from 1 to 9 is 8:</em>
Let
be those digits, then:

- <em>If 9 is added to a number then both the digits become equal. find the number:</em>
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But from eq 1:

Substituting y into the expression 1:

The x-value will be found by hit and trial, so:

We have to reject this solution because digits are different.

We have to reject this solution because digits are different.

<em>Then this is a two digit number formed by two equal digits. </em>
Finally, the number is:
44
B you can tell just by look x^2*x^2=x^4
Rate of change = slope
slope = )y2 - y1) / (x2 - x1)
(0,-4)....x1 = 0 and y1 = -4 (pay attention to the negative sign when subbing)
(3,2)....x2 = 3 and y2 = 2
now we sub
slope(rate of change) = (2 - (-4) / (3 - 0) = (2 + 4) / 3 = 6/3 = 2 <==