The explicit formula for arithmetic sequence is:
an=a+(n-1)d
where:
a=first term
d=common difference
given:
a3=22
a(17)=-20
substituting this in our equation we get:
22=a+(3-1)d
22=a+2d
a=22-2d........i
also:
-20=a+(17-1)d
-20=a+16d.....ii
but substituting i in ii we get:
-20=22-2d+16d
-20-22=14d
-42=14d
d=-3
but:
a=22-2d
a=22-2(-3)
a=28
thus the formula will be:
an=28-3(n-1)
thus the first term will be 28
the 2nd term will be:
a2=28-3(2-1)
a2=25
the 3rd term will be:
a3=28-3(3-1)
a3=28-6
a3=22
a4=28-3(4-1)
a4=28-9
a4=15
a5=28-3(5-1)
a5=28-3(4)
a5=28-12
a5=15
Yes 2/4 is less than 2/3 :) I hope this helps
Answer:
B. A dilation with a scale factor of 0.5
Step-by-step explanation:
A. is wrong because it is congruent transformation because reflections keep the angles and side lengths of the figure the same.
B. is right because it is NOT congruent because a dilation of any scale factor other than 1 results in a similar figure, because the side lengths are proprtional but not equivalent
C. is wrong because translations keep the angles and side lengths of the figure the same.
D. is wrong because a scale factor of 1 changes nothing about the figure.
This diagram shows how 2/7 = 8/28 by showing that you can color in more squares or duplicate that amount of squares 4 times in order to get 8/28. (Since 2/7 x 4/4 = 8/28.)
