PLEASE HELP ME I WILL MARK BRAINLIEST

$36

Step-by-step explanation:

I think the part that is confusing you is how to read the math syntax.

The part that says "" just means that a=1 is your starting number. The n=1 is the first iteration.

The part that says "" just means that you add 5 to the previous number every iteration.

They want you to find the number at 8th iteration, n=8. So lets work it out.

n=1:  a= 1

n=2: a= 1+5 = 6

n=3: a= 6+5 = 11

n=4: a= 11+5 = 16

n=5: a= 16+5 = 21

n=6: a= 21+5 = 26

n=7: a=26+5 = 31

n=8: a= 31+5 = 36

Or you can use the shortcut:

You're always adding by 5 each time and starting with 1, so:

where n=8 for the 8th round.

starting with:    

5 + x - 12 = 2x - 7   

5 + x - 12 - x = 2x - 7 - x (subtract x from both sides)   

5 - 12 = x - 7 (combine and cancel x's from both sides)   

5 - 12 + 7 = x - 7 + 7 (add 7 to both sides)   

0 = x (add numbers together on both sides)       

so in order for the equation to be true, x must be 0.   

trying x = -0.5   

5 + x - 12 = 2x - 7 (original equation)   

5 + -0.5 - 12 = 2(-0.5) - 7 (plug in value of x)   

5 + -0.5 - 12 = -1 - 7 (did multiplication)   

-7.5 = -8 (did addition on both sides)       

since -7.5 is obviously not equal to -8, the value of -0.5 for x is wrong.   

trying x = 0   

5 + x - 12 = 2x - 7 (original equation)   

5 + 0 - 12 = 2(0) - 7 (plug in value of x)   

5 + 0 - 12 = 0 - 7 (did multiplication)   

-7 = -7 (did addition on both sides)       

since -7 equals -7, that demonstrates that the value of 0 for x is correct.   

trying x = 1   

5 + x - 12 = 2x - 7 (original equation)   

5 + 1 - 12 = 2(1) - 7 (plug in value of x)   

5 + 1 - 12 = 2 - 7 (did multiplication)   

-6 = -5 (did addition on both sides)       

since -6 is obviously not equal to -5, the value of 1 for x is wrong.