The 12th term of the arithmetic sequence is 10.5. The 18th term of this sequence is 13.5. Find the common difference and the first term.

let the n'th term be called x, and the value of the term y,

then there is a function y=a*x + b

that will give us all term we want.

this formula is also used for straight lines.

we just need a and b. we already got two data points. we can just plug the known x/y pairs into the formula

10.5 = a*12 + b

13.5 = a*18 + b

now lets manipulate these lines.

multiply the first line by 3 and the second line by 2

31.5 = a*36 + 3b

27 = a*36 + 2b

subtract the second line from the first line

4.5 = b

yey, we now know b, let's plus b into either line from above, I'll go with the first one, looks easier.

10.5 = a*12 + 4.5

6 = a*12

0.5 = a

now y=a*x + b can be filled with a and b

y = 0.5 * x + 4.5

for x=1 (the first term) it's f(1)=5

each step is 0.5, hence the common difference.

(13.5-10.5)/(18-12)

= 3 / 6

= 0.5

we got the comment difference by looking at the full difference over 6 steps and divined by these 6 steps.

from step 12 to step one it's 11 steps down

10.5 - 0.5*11

= 10.5 - 5.5

= 5

the most boring ever written

step-by-step explanation:

i am writing something. yes, i plan to make it the most boring thing ever written. i go to the store. a car is parked. many cars are parked or moving. some are blue. some are tan. they have windows. in the store, there are items for sale. these include such things as soap, detergent, magazines, and lettuce. you can enhance your life with these products. soap can be used for bathing, be it in a bathtub or in a shower. apply the soap to your body and rinse. detergent is used to wash clothes. place your dirty clothes into a washing machine and add some detergent as directed on the box. select the appropriate settings on your washing machine and you should be ready to begin. magazines are stapled reading material made with glossy paper, and they cover a wide variety of topics, ranging from news and politics to business and stock market information. some magazines are concerned with more recreational topics, like sports card collecting or different kinds of hairstyles. lettuce is a vegetable.

the answer for this question is : 360°

step-by-step explanation:

we have been given a triangle   we need to tell which one of these is a triangle below to map onto itself.

360° rotation is the complete rotation which eventually leads to the same figure which is given.

the correct will be, that is 360° that will cause the triangle below to map onto itself.