Answer:
If there is 1 at the top, then you have 1, then 2, then 3, etc.
total number of oranges equals:
1 + 2 + 3 + ... + 16 + 17 + 18 <-- stop at 18 because this is the number of oranges at the base
You can use the formula:
sum of first n numbers = n*(n + 1)/2
-->
18*19/2 = 9*19 = 171
or you can figure it out (basically derive the above formula):
you have:
1 + 18 = 19
2 + 17 = 19
3 + 16 = 19
...
How many pairs do you have? Well, it's just the number of numbers: 1-18 = 18 numbers (divide by 2) = 9 pairs)
9 pairs of 19 = 9 * 19 = 171
Hope this helps!
Step-by-step explanation:
1 and 1/4 cup of raisins and 2 and 1/2 cups of nuts for a total of 3 and 3/4 cups.
Answer:
bags of snack = x = 6
bottles of water = y = 5
Step-by-step explanation:
The system of equations can be used to determine how many of each item they bought.
20.00=2.50x+1.00y
11=x+y
how many bags of snack mix did they buy?
Let
bags of snack = x
bottles of water = y
20.00 = 2.50x + 1.00y (1)
11 = x + y (2)
From (2)
x = 11 - y
Substitute x = 11 - y into (1)
20.00 = 2.50x + 1.00y
20.00 = 2.50(11 - y) + 1.00y
20.00 = 27.5 - 2.50y + 1.00y
20.00 - 27.5 = -2.50y + 1.00y
-7.5 = -1.5y
y = -7.5/-1.5
y = 5
Substitute y = 5 into (2)
11 = x + y
11 = x + 5
11 - 5 = x
x = 6
bags of snack = x = 6
bottles of water = y = 5
Answer:
The area of the triangle is of 8 units of area.
Step-by-step explanation:
Answer:
The area of the triangle is of 21 units of area.
Step-by-step explanation:
The area of a triangle with three vertices 
is given by the determinant of the following matrix:
In this question:
Vertices (1,0) (5,0) (3,4). So
The area of the triangle is of 8 units of area.
You'll want to use the quadratic formula:
-b (+/-) sqrt(b^2 - 4ac), all divided by 2a.
Under the square root you'll get:
-11
remember that the square root of -1 is i.
sqrt(-11) can be factored to sqrt(11*-1) and then sqrt(-1) * sqrt(11)
which becomes i*sqrt(11)
so your complex solution is:
-3 (+/-) (i*sqrt(11)), all over 4
