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.
She pays 9.6 euros. Hope this helped, could I possibly get brainliest?
Answer: x = 3
Step-by-step explanation:
First you need to start by adding positive 4x to both sides since the 4x is a negative. 4x + (-7x) = -3x. Then it is just simply -3x+2 = -7. Since 2 is a positive number subtract both both sides by 2. Then you should get -3x = -9. Then divide both sides by -3 and the answer is x = 3.
No,27.93 equals <span>20.00+7.00+0.9+0.03</span>
