The veretx is normally the minimum value
hack:
for f(x)=ax²+bx+c
the x value of the vertex is -b/2a
so
f(x)=1x²-16x+71
x value is -(-16)/(2*1)=16/2=8
find f(8) to find y value of vertex
f(8)=8²-16(8)+71
f(8)=64-128+71
f(8)=7
the vertex is (8,7)
the minimum value is 7
<h3>Key points :-</h3>
᪥ The formula to find the 31st term is : 
᪥ In the formula, 
represents the first term of the sequence.
᪥ 
is the number of terms, In our case n is 31.
᪥ 
is the common difference between the terms, In our case d is 4.
<em>Detailed Solution is attached</em>᭄
*edit
Answer:
4/5
Step-by-step explanation:
you'd do 4 divided by 2 which is 2, then you'd do 10 divided by 2 which is 5. so you get 4/5.
Answer:
e=14
Step-by-step explanation:
15/21 =10/e
by cross multiplying,
e×15=21×10
15e=210
e=210/15
e=14
