Answer:
The equation for the nth term of the given arithmetic sequence is: 
Step-by-step explanation:
We need to write an equation for the nth term of the arithmetic sequence:
15,28,41 ....
The equation for arithmetic sequence is: 
Where
is the nth term,
is first term and d is common difference
In the given sequence we have:
a₁ = 15
a₂ = 28
We can find common difference using the formula:

So, the common difference d is 13
Now, equation for nth term will be:

So, the equation for the nth term of the given arithmetic sequence is: 
where n=1,2,3..
Pythagorean theorem - a^2 + b^2 = c^2
2^2+3^2 = d^2
d^2 = 13
d= square root of 13
The second answer is 4 times as small as the first
X-4y=-12
4x-y=12
eliminate y's
multily 2nd equaiton by -4 and add to top one
x-4y=-12
<u>-16x+4y=-48 +
</u>-15x+0y=-60
-15x=-60
divide both sides by -15
x=4
sub back
x-4y=-12
4-4y=-12
minus 4 both sides
-4y=-16
divide both sides by -4
y=4
x=4
y=4
(x,y)
(4,4)<u>
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