The area of a circle is:

"r" being the radius and π being 3.14
14. The diameter is 12. So, to get the radius, we would need to halve it. So, the radius would be 6.
Now we plug in 6 for r and 3.14 for π which makes it

which equals 113.04
15. The diameter is 9, so to get the radius we need to halve it to get 4.5
Plug in 4.5 for r and 3.14 for π and we get

which equals 63.585
16. The diameter is 18, so to get the radius we need to halve it to get 9
Plug in 9 for r and 3.14 for π and we get

which equals 254.34
17. The diameter is 8, so to get the radius we need to halve it to get 4.
Plug in 4 for r and 3.14 for π and we get
1. 7+ (-9) = 7-9=-2
2.(-8) + (+5)= -8+5= -(8-5)=-3
3.(+9) - (-3) = 9+3=12
4.(+12) - (-1) = 12+1=13
5. (-7) - (-5) = -7+5==(7-5)=-2
<span>(-14) - (+2) = -14-2=-(14+2)=-16</span>
When they're all distributed and simplified they both equal 6x+12
You can read 100 pages in 5 hours.
40 pages in 2 hours. We need to get the unit rate. In this case, we need to get the number of pages read in 1 hour.
40 pages ÷ 2 hours = 20 pages per hour.
20 pages per hours * 5 hours = 100 pages.
Surprisingly, a one-step equation <em>is </em>that simple; it's just an equation that takes one step to solve. So yes, 3 + 4 = 7 would be one you could do. You could also do a simple multiplication or division problem if you'd like, for instance you could do 4*3=12, or 12/4=3. Hope I helped!