(2,7)
(6,12)
(10,17)
Some moderator deleted my response for some reason. I did it mentally.. but I guess I'll show proof.
1) (2,7)
-4y = -5x - 18
-4(7) = -5(2) - 18
-28 = -10 -18
-28 = -28
2) (6,12)
<span>-4y=-5x-18
</span> -4(12) = -5(6) - 18
-48 = -30 - 18
-48 = -48
3) (10,17)
4y=-5x-18
-4(17) = -5(10) - 18
-68 = -50 - 18
-68 = -68
See the pattern? 2,6,10 and 7,12,17?
Done with substitution and trial and error :3333
6*6 = 36. 36 * 3.14 = 113.04. Now, 113.04*2 = 226.08.ft^3. The Answer Is 226.08ft^3.
<h3>
Answer: 9 months</h3>
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Work Shown:
100 + 22x = 298
22x = 298-100 ........ subtracting 100 from both sides
22x = 198
x = 198/22 .............. dividing both sides by 22
x = 9
It will take 9 months for her to pay off the sofa.
She pays the original $100, and then on top of that, she pays an extra 22*x = 22*9 = 198 dollars since she paid $22 per month for 9 months. So this leads to 100+198 = 298 dollars total to help confirm our answer.