9514 1404 393
Answer:
5 hours
Step-by-step explanation:
A quick way to look at this is to compare the difference in hourly charge to the difference in 0-hour charge.
The first day, the charge is $3 more than $12 per hour.
The second day, the charge is $12 less than $15 per hour.
The difference in 0-hour charges is 3 -(-12) = 15. The difference in per-hour charges is 15 -12 = 3. The ratio of these is ...
$15/($3/h) = 5 h
The charges are the same after 5 hours.
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If you write equations for the charges, they will look like ...
y1 = 15 + 12(x -1)
y2 = 3 + 15(x -1)
Equating these charges, we have ...
15 +12(x -1) = 3 + 15(x -1)
12x +3 = 15x -12 . . . . . . . . eliminate parentheses
15 = 3x . . . . . . . . . . add 12-12x
x = 15/3 = 5 . . . . . . divide by 3
You might notice that the math here is very similar to that described in words, above.
The charges are the same after 5 hours.
Answer: 30 m ; (or, write as: "30 meters") .
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Explanation:
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Area of a trapezoid, "A" = (1/2) ( b₁ + b₂) h ;
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or, write as: A = ( b₁ + b₂) h / 2 ;
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in which: A = area;
b₁ = length of "base 1" (choose either one of the 2 (two bases);
b₂ = length of "base 2" (use the base that is remaining);
h = height of trapezoid;
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From the information given:
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A = 100 m² ;
h = 5 m
b₁ = 10 m
b₂ = x
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Find "x", which is: "b₂" ;
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A = ( b₁ + b₂) h / 2 ;
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Plug in our known values; and plug in "x" for "b₂" ; and solve for "x" ;
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100 m² = [(10m + x) (5m)] / 2 ; Solve for "x" ;
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(10m + x) (5m) = (2)* (100m²) ;
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(5m) (10m + x) = 200 m² ;
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Note: The distributive property of multiplication:
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a(b+c) = ab + ac ;
a(b−c) = ab <span>− ac ;
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We have: (5m) (10m + x) = 200 m² ;
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So: (5m) (10m + x) = (5m*10m) + (5m * x) ;
= 50m² + (5m)x ;
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→ 50m² + (5m)x = 200m² ;
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Divide the ENTIRE equation by "5m" ;
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→ { 50m² + (5m)x } / 5m = (200m² / 5m) ;
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→ 10m + x = 40m ;
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Now, subtract "10m" from EACH side of the equation; to isolate "x" on one side of the equation; and to solve for "x" ;
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→ 10m + x − 10m = 40m − 10m ;
to get:
→ x = 30 m ; which is our answer.
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Answer: 30 m ; (or, write as: "30 meters") .
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The slope of the line is 3/2. That would be letter B. You take two points from the graph and subtract them from each other to find the slope. Hope this helps!
Every square is a rectangle<span> because it is a quadrilateral with </span>all<span> four angles right angles.</span>
