<h2><u>Part A:</u></h2>
Let's denote no of seats in first row with r1 , second row with r2.....and so on.
r1=5
Since next row will have 10 additional row each time when we move to next row,
So,
r2=5+10=15
r3=15+10=25
<u>Using the terms r1,r2 and r3 , we can find explicit formula</u>
r1=5=5+0=5+0×10=5+(1-1)×10
r2=15=5+10=5+(2-1)×10
r3=25=5+20=5+(3-1)×10
<u>So for nth row,</u>
rn=5+(n-1)×10
Since 5=r1 and 10=common difference (d)
rn=r1+(n-1)d
Since 'a' is a convention term for 1st term,
<h3>
<u>⇒</u><u>rn=a+(n-1)d</u></h3>
which is an explicit formula to find no of seats in any given row.
<h2><u>Part B:</u></h2>
Using above explicit formula, we can calculate no of seats in 7th row,
r7=5+(7-1)×10
r7=5+(7-1)×10 =5+6×10
r7=5+(7-1)×10 =5+6×10 =65
which is the no of seats in 7th row.
Krista will have more money in 2 years time than Nick and she will get $14.05 more than Nick. Hope this helps.
The answer would probably be D because you don't know what x is.
3.) 3, 4, 5
&
4.) 6, 8, 10
Those two are right triangles because when you add the squares of the first two it should give you the square root of the third number
a^2 + b^2 = c^2
So
3^2 + 4^2 = 5^2
9 + 16 = 25
25 = 25
6^2 + 8^2 = 10^2
36 + 64 = 100
100 = 100
Therefore they are right triangles
But 1 & 2 aren’t right triangles because when you add the squares of the first two number, it doesn’t equal to the square root of the third number.
Hope this helps!!