Answer:
(5x+20)+(4x-11)=180(linear pair)
9x+9=180
9x=180-9
9x=171
x=171/9
x=19
now,
(2y+19)+(5x+20)=180(co-interior angle)
2y+19+5×19+20=180
2y+134=180
2y=180
y=180/2
y=90
Triangular sequence = n(n + 1)/2
If 630 is a triangular number, then:
n(n + 1)/2 = 630
Then n should be a positive whole number if 630 is a triangular number.
n(n + 1)/2 = 630
n(n + 1) = 2*630
n(n + 1) = 1260
n² + n = 1260
n² + n - 1260 = 0
By trial an error note that 1260 = 35 * 36
n² + n - 1260 = 0
Replace n with 36n - 35n
n² + 36n - 35n - 1260 = 0
n(n + 36) - 35(n + 36) = 0
(n + 36)(n - 35) = 0
n + 36 = 0 or n - 35 = 0
n = 0 - 36, or n = 0 + 35
n = -36, or 35
n can not be negative.
n = 35 is valid.
Since n is a positive whole number, that means 630 is a triangular number.
So the answer is True.
Answer:
7 digits can be used for each position
There are a total of 5 positions
N = 7^5 = 16,807 numbers
You have 7 choices for the first position, second position, etc.
Answer:
$2.40
Step-by-step explanation:
$12.00÷100=0.12x20=2.4
hope this helps, have a good day.
