Answer:
1620
Step-by-step explanation:
The amount of even integers between 10 and 80 inclusive is 36 (5 for each interval of 10 [e.g., 10-19 has 5, 20-29 has 5] and one extra for 80).
Since the numbers are consecutive even numbers, we can use the fact that the sum of the numbers is equal to the average of the numbers, times the number of numbers.
The average of the numbers is 45, since
. We can use only the two outer numbers to determine the average since the numbers are all evenly spaced as they are consecutive even numbers.
, so the sum is 1620.
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.
7 - 4 = 3 that will be your answer