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:
The area of the rectangle on the left side is
The area of the bottom rectangle is
The total area of the composite figure will be
Step-by-step explanation:
The area of any given rectangle can be found by multiplying the length of that rectangle by its width. The rectangle on the left side has a length of 9cm but the width is unknown. To find the width, we subtract 6cm from the width of the bottom rectangle: 10cm. And that gives us 4cm.
Therefore, we can now calculate the area to be: length × width = 9cm × 4cm = 36cm²//
The area of the bottom rectangle can be found similarly by multiplying the length: 2cm by the width: 6cm of that rectangle. And the result gives us: 2cm × 6cm = 12cm²//
The total area of the composite figure is calculated by adding the results from the left and bottom rectangles together. And that gives us: 36cm² + 12cm² = 48cm²//
Answer:
C
Step-by-step explanation:
y-3=5(x-2) (rearrange this to be in slope- intercept from) (add 3 to both sides)
y = 5(x-2) + 3 (distribute parentheses)
y = x(5) - 2(5) + 3
y = 5x -10 + 3
y = 5x - 7
recall that for a line with gradient m, the gradient of the perpendicular line will be - (1/m)
hence in our case, our gradient of the original line is 5, hence the gradient of the perpendicular line is -1/5
From the choices, the only one that is consistent with this is C
i.e choice C:
5y + x = 25
5y = -x + 25
y = -(1/5) x + 5 ===> gradient of -1/5
Is it not zero ???? ? ? ?
A. -4/1=-4
And -4 is the slope
