Answer:
The answer to your question is: length = 14 ft; width = 3 ft
Step-by-step explanation:
Data
Area = 42 ft²
length = 8 + 2w
w = width = ?
length = ?
Formula
Area = length x width = l x w
Substitution
42 = (2w + 8)w
42 = 2w² + 8w
2w² + 8w - 42 = 0
Dividing by 2
w² + 4w - 21 = 0 Factorize
(w + 7) (w - 3) = 0
w1 = -7 w2 = 3
It's not possible to have negative widths
So the answer is w = 3 ft
length = 2(3) + 8
length = 6 + 8
length = 14 ft
Answer:
2.069x10^3
Step-by-step explanation:
Move the decimal places.
Answer:
–x² + 12x + 5
Step-by-step explanation:
x² + 3x
–2x² + 9x + 5
The sum of the above expression can be obtained as follow:
.... x² + 3x
+ –2x² + 9x + 5
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
–x² + 12x + 5
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Thus, the sum of x² + 3x and –2x² + 9x + 5 is –x² + 12x + 5
