What is the sum of the first 18 terms in the arithmetic sequence 3+7+11+...? What are the coordinates of the point where the line y = -\frac{4}{5}x + 80 intersects the x -axis?

71

Step-by-step explanation:

I am only able to really help with the first part of this question. I am very sorry about that!

Lets take a look at the sequence!

It starts with 3 and then goes to 7. Which means it is adding 4 each time it continues. To confirm this, lets look at 11. 7 goes to 11, which again means it is adding 4! So we understand and now the pattern!

Rather than doing a buttload of work, lets do it an easier way. Lets plug 18 into a  calculator!

If you have one, all you need to do is add 3 plus 4. Then plus for again. That should start a ripple effect if you press enter. On the 18 term it would be 71!

Hope that helped.

that is the sum

step-by-step explanation:

there are no other answers without knowing the variables values

set each factor equal to 0

4x-3 = 0

2x-1 = 0

solve for x.

4x-3=0

4x=3

x= 3/4

solve for x. 

2x-1= 0

2x= 1

x= 1/2

eventually after a few more steps, your answer should be 1/2 is less than or equal to x and 3/4 is greater than or equal to x