It 13 because you subtract 6 from 74.25 and then divide by 5.25
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We calculate the speed by dividing the distance over time:
s = d/t
So the distance described in the problem is always the same, A to B and B to A.
But we are told that;
7 = d/t
7 = 2d/(t + 2)
that is, the first equation say that at speed 7 km/h a distance d is walked in a time t
the second equation say that at a average speed of 7 (that is 8 on one way and 6 in the other: 8 + 6 = 14, half of it), twice the distance is walked in a time equal to the first time plus 2 minutes.
So we have a system of linear equations, 2 of them with two unknowns, we can solve that:
7 = d/t
7 = 2d/(t + 2<span>)
</span>lets simplify them:
7t = d
7(t + 2) = 2d
7t = 2d - 14
we substitute the first in the second:
<span>7t = 2d - 14
</span><span>7t = d
</span>so:
d = 2d - 14
d = 14
so the distance between A and B is 14 km
Answer: x = -0.3
Step-by-step explanation:
<u>Given expression</u>
1 - 3 (9x + 3) = 3x + 1
<u>Expand parentheses and apply the distributive property</u>
1 - 27x - 9 = 3x + 1
<u>Combine like terms</u>
(1 - 9) - 27x = 3x + 1
-8 - 27x = 3x + 1
<u>Subtract 3x on both sides</u>
-8 - 27x - 3x = 3x + 1 - 3x
-8 - 30x = 1
<u>Add 8 on both sides</u>
-8 - 30x + 8 = 1 + 8
-30x = 9
<u>Divide - 30 on both sides</u>
(-30)x / (-30) = 9 / (-30)
(-30)x / (-30) = 3 / (-10)
Hope this helps!! :)
Please let me know if you have any questions
