Answer:

It's change of subject. :)
Answer:
A
Step-by-step explanation:
Given
20 - || - 13 | + 17 |
Note the absolute value function always returns a positive value, that is
| - a | = | + a | = a, thus
= 20 - | | - 13 |+ 17 |
= 20 - | 13 + 17 |
= 20 - | 30 |
= 20 - 30
= - 10 → A
Not sure what the length of the rectangle is but to find perimeter of a rectangle you can use the following formula
2w+2l= perimeter
The reason we multiply both the length and width by two is because there are two ends of the width and two ends of the length.
The other formula that would also work is as follows
w+w+l+l= perimeter
Hope it helps
Answer:
one solution! & that would be be 57/10. hopefully that's correct.
Step-by-step explanation:
Answer:
x = 8
y = 11
Step-by-step explanation:
Total small box weight = 50x [x being the number of small boxes]
Total large box weight = 80y [y being the number of large boxes]
Total boxes = x+y = 19
Total weight = 1280
<em>Determine x and y.</em>
<u>You know 2 equations. One for weight and another for number of boxes each.</u>
<u>Rewrite second equation:</u>
x+y=19
y=19-x
<u>You have to plug in one into another.</u>
1280 = 50x + 80(19-x)
<u>Solve for x</u>
1280 = 50x + 1520 - 80x
-240 = -30x
x = 8
<u>Solve for y by plugging in x into one of the equations:</u>
8+y = 19
y = 11