The answer is C because -2 is less than or equal to 5. (4 times 0 is 0)
Answer:
x= -4
Step-by-step explanation:
Answer:
x=71
Step-by-step explanation:
38+x+x=180
x+x=142
2x=142
x=71
Answer:
- 525 = (w+4)(w)
- 21 ft by 25 ft
Step-by-step explanation:
Let w represent the width of the floor. Then the length of the floor is (w+4) and its area is ...
A = LW
525 = (w+4)(w)
w^2 +4w -525 = 0
(w -21)(w +25) = 0 . . . . factor the above
Solutions are ...
w = 21, w = -25
We are interested in the positive solution: w = 21.
The floor is 21 feet wide and 25 feet long.
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<em>Alternate solution</em>
Sometimes, when the factors aren't obvious, it works well to write an equation for the average of the dimensions. Here, we can represent that with x, and use (x-2) for the width, and (x+2) for the length. Then we have ...
525 = (x-2)(x+2) = x^2 -4
529 = x^2
√529 = 23 = x
Then w=23 -2 = 21, and the length is w+4 = 25.
