Answer: ummm i think it's -1
Step-by-step explanation:
Answer:
17/7, y = 21 * (17/7), 51
Step-by-step explanation:
so to find what x is, we need to find how much it rises in 1 minute. we do that by dividing 17 by 7. we then see that we want to find how much is it filled in 21 minutes. we then multiply (17/7) by 21 to find the y which is 51
D.
first, eliminate B and C, because the highest degree in these two equation is 3, a 3-degree equation has 3 roots, not 4.
between A and D, A has the roots 0, 0, 7, and -7, all real roots.
D can be factored into (x²-49)(x²+1)=0
x²=49 or x²=-1
x=7 or -7, x=i or -i two real roots, two unreal roots
for the second equation:
first, find the first term by using the formula:
the nth term=the first term + (n-1)*difference
you are given the 13th term and d=3.7
a13=a1+(13-1)d
1.9=a1+12*3.7
a1=-42.5
the sum of the first 13 terms is S=(a1+a13)*(13/2)=(-42.5+1.9)*6.5=-263.9