Answer:
115
Step-by-step explanation:
There is a common difference d between consecutive terms, that is
d = 7 - 1 = 13 - 7 = 19 - 13 = 25 - 19 = 6
This indicates the sequence is arithmetic with n th term
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = 1 and d = 6 , thus
a₂₀ = 1 + (19 × 6) = 1 + 114 = 115
The solutions or roots to this equation is found by solving for x. We can do this a couple ways either by FOIL or quad formula
3x^2+6x+6=0
3(x^2+2x+2)=0
x^2+2x+2=0 we cant FOIL this out so we use the quad formula
x= [(-b+\-sqrt(b^2-4ac))/2a]
x= -2+\- sqrt(4-4(1)(2))/2(1)
x= -1 +i , -1 - i
So we have complex roots since our quad formula returned a negative number. Whenever the quad formula answer is positive we have two roots/solutions, when it is zero we have one root/solution, and whenever it is negative we have Complex roots/solutions
Hope this helps. Any questions please just ask. Thank you.
Hey there,
It take 45 min to complete 75% of the wall
1% = 45 / 75
= 0.6
100 % = 0.6 x 100
= 60 min
It takes her 60 mins or 1 hour to finish building the wall.
Hope this helps :))
~Top♥
2n+1=2n+3=2n+5=2n+7-64
4nexponet2+8n+34exponetof2+25+34-64
8n+3=24n-29
16n=32
n=2
Hence option a I believe is true
