Answer:
- width: 18 in
- length: 27 in
Step-by-step explanation:
The relations between length (L) and width (W) are ...
W +9 = L
LW = 486
Substituting gives ...
(W+9)W = 486
W^2 +9W -486 = 0 . . . put in standard form
(W +27)(W -18) = 0 . . . . factor
W = 18 . . . . the positive solution
The width of the rectangle is 18 inches; the length is 27 inches.
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<em>Comment on factoring</em>
There are a number of ways to solve quadratics. Apart from using a graphing calculator, one of the easiest is factoring. Here, we're looking for factors of -486 that have a sum of 9.
486 = 2 × 3^5, so we might guess that the factors of interest are -2·3² = -18 and 3·3² = 27. These turn out to be correct: -18 +27 = 9; (-18)(27) = -486.
The simple and easiest way to find it is that you add all the numbers of that value i.e.: 1485=1+4+8+5 it will give u a number which will tell u if it is divisible by what number i mean that: 1+4+8+5=18 so 18 is divisible by 2, 3, 6, and 9
Answer:
D) 8x²-172x+120
Step-by-step explanation:
Length=2(-2x+20)+6
Width=-2x+20
(-4x+40+6)(-2x+20)
(-4x+46)(-2x+20)
8x²-80x-92x+920
8x²-172x+920
(5 + 6)3 would represent what you want.
This is how I would solve it, I would act as if there were 36 people in the class.
36÷6=6×5=30
30÷3=10×2=20
20/36=10/18=5/9
You could also try another number such as 24;
24×(5÷6)=20
20×(2/3)=13.3(3 repeating)
13.333/24=5/9
5/9 people have dogs.
Tell me if this helps.