In the first series, the summation applies to the whole (2n+3) inside
the parentheses, so the 3 gets summed up 5 times.
But in the second one, the summation only applies to the 2n , so
the 3 is only added after the summation is finished.
The difference between five 3s the first time and one 3 the second time
is your 12 .
Answer:
Step-by-step explanation:
Here's the game plan. In order to find a point on the x-axis that makes AC = BC, we need to find the midpoint of AB and the slope of AB. From there, we can find the equation of the line that is perpendicular to AB so we can then fit a 0 in for y and solve for x. This final coordinate will be the answer you're looking for. First and foremost, the midpoint of AB:
and
Now for the slope of AB:
and
So if the slope of AB is 1/3, then the slope of a line perpendicular to that line is -3. What we are finding now is the equation of the line perpendicular to AB and going through (0, 3):
and filling in:
y - 3 = -3(x - 0) and
y - 3 = -3x + 0 and
y - 3 = -3x so
y = -3x + 3. Filling in a 0 for y will give us the coordinate we want for the x-intercept (the point where this line goes through the x-axis):
0 = -3x + 3 and
-3 = -3x so
x = 1
The coordinate on the x-axis such that AC = BC is (1, 0)
Answer:
-2
Step-by-step explanation:
-5 + 3 = -2
If you have any questions about the way I solved it, don't hesitate to ask me in the comments below :)
Answer: 197
Step-by-step explanation:
The nth term is 3n+5
so the 64th term will be
(3 x 64)+5
192+5
= 197