X=18 (3/8)
(8x/7) +9 = 30
subtract 9 from both sides
8x/7=21
multiply 7 from both sides
8x=147
divide 8 from both sides and you get
x=18 (3/8)
Answer:
36
Step-by-step explanation:
The number of two of the nine members of ski patrol unit can be chosen is equal to the combinations of 9 taken 2. This can be calculated using the formula:
=
, where
9! =9×8×7×6×5×4×3×2×1 and
7!=7×6×5×4×3×2×1
2!=2×1 then the equation becomes:
=
=36
We know that the area is 20.
Since 20 is a small number: lets list out possible combinations of lengths and widths.
1 * 20
2 * 10
4 * 5
L = 7 + 3w
lets see which on makes sense.
L = 7 + 3w
20 = w7 + 3w^2
3w^2 + 7w -20 = 0
(3w - 10)(w - 2)
w can equal 10/3 or 2.
So the dimensions: are Width = 2 Length = 10