Answer:
B) (4x-5i)(4x+5i)
Step-by-step explanation:
The expression can be treated as the difference of squares, and factored accordingly. That factoring is ...
a² -b² = (a -b)(a +b)
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Here, we have ...
a² -b² = 16x² -(-25)
a² = 16x² ⇒ a = 4x
b² = -25 ⇒ b = √-25 = 5i
Then the factoring is ...
(a -b)(a +b) = (4x -5i)(4x +5i)
Answer:
2 x 7
Step-by-step explanation:
a * b = 14
2a + 2b = 18
(a * b)/b = 14/b Dividing both sides by b
a = 14/b
Substitute a in the perimeter equation
2(14/b) + 2b = 18
28/b + 2b = 18
2b - 18 + 28/b = 0
Multiply both sides by b
2b^2 - 18b + 28 = 0
Divide both sides by two
b^2 - 9b + 14 = 0
The Factors of 14 include -2 and -7 which add up to -9
(b - 2) * (b - 7) = 0
This has two answers because b can be either the side that is 2 long or 7 long, so there's no need to go back and solve for a.
2 x 7
They already spent $2000, and they only had $5100
Subtract
5100 - 2000 = 3100
$3,050 is your answer, because it is the only one that is less than 3100
hope this helps