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.
_____
<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.
It would first be 0.7 and then 1.1
Answer:
24%
Step-by-step explanation:
Difference in price of sweater
=$25-$19
=$6
6/25×100%=24%
For this case we have a direct variation of the form:

Where,
- <em>k: proportionality constant
</em>
We must find the value of k.
For this, we use the following data:

Therefore, replacing values we have:

Rewriting:

Clearing the value of k we have:

Therefore, the direct variation equation is given by:

Answer:
The quadratic variation equation for the relatonship is:
