Answer:
So Philip made 5 bracelets and 4 necklaces.
Step-by-step explanation:
Let x = number of bracelets and y = number of necklaces.
Since we have a total of 9 bracelets and necklaces,
x + y = 9 (1)
Also, we have 8 inches of cord for each bracelet and 20 inches of cord for each necklace, then the total length for the bracelet is 8x and that for the necklace is 20y.
So, the total length for both is 8x + 20y. Since the total length of cord used is 120 inches,
8x + 20y = 120 (2)
Simplifying it we have
2x + 5y = 30 (3).
Writing equations (1) and (3) in matrix form, we have
Using Cramer's rule to solve for x and y,
x = (9 × 5 - 30 × 1) ÷ (1 × 5 - 1 × 2)
x = (45 - 30) ÷ (5 - 2)
x = 15 ÷ 3
x = 5
y = (30 × 1 - 9 × 2) ÷ (1 × 5 - 1 × 2)
y = (30 - 18) ÷ (5 - 2)
y = 12 ÷ 3
y = 4
So Philip made 5 bracelets and 4 necklaces.
Answer:
324
Step-by-step explanation:
4×3=12
12×3=36
36×3=108
108×3=324
it's being multiplied by 3's
Ooh, fun
geometric sequences can be represented as
so the first 3 terms are
the sum is -7/10
and their product is -1/125
from the 2nd equation we can take the cube root of both sides to get
note that a=ar/r and ar²=(ar)r
so now rewrite 1st equation as
subsituting -1/5 for ar
which simplifies to
multiply both sides by 10r
-7r=-2-2r-2r²
add (2r²+2r+2) to both sides
2r²-5r+2=0
solve using quadratic formula
for
so
for 2r²-5r+2=0
a=2
b=-5
c=2
so
or
use them to solve for the value of a
try for r=2 and 1/2
or
test each
for a=-1/10 and r=2
a+ar+ar²=
it works
for a=-2/5 and r=1/2
a+ar+ar²=
it works
both have the same terms but one is simplified
the 3 numbers are
,
, and
Step-by-step explanation:
The first set is equivalent.
We obtain the right-hand side by swapping places of the terms.