Answer:

Step-by-step explanation:
we know that
The formula to find the sum is equal to

where
a1 is the first term
an is the last term
n is the number of terms
In this problem we have



substitute the values in the formula

1) 50 × 2 = 100
2) 60×20= 1200
3) 70×20=1400
Hope this helps
The inequality x>35 represents the problem
more than is: >
Answer: Direction opens downward
Step-by-step explanation:
X-Intercept: (1/14,0),(-1/4,0)
Y-Intercept: (0,1)
Find the vertex using x= -b/2a
Plug it into the vertex form = y=a(x-h)^2 +k
H,K will identify the direction.