Here ya go, I hope this helps :)

The sign at the end changes because both sides of the equation are being divided by a negative number.
Answer:
=3.162
Step-by-step explanation:
x2
= −0 + √ 02 − 4×1×(−10)
2×1
= 0 + 2 × √ 10
2
= 3.162
Answer: The answer is A
Step-by-step explanation: 4c+6a<120 and 4c+4a<100
Answers:
hypotenuse = 20 feet
longer leg = 16 feet
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Explanation:
c = x = length of the hypotenuse
a = x-4 = length of one of the legs
b = 12 = length of the other leg
Use the pythagorean theorem
a^2 + b^2 = c^2
12^2 + (x-4)^2 = (x)^2
144 + x^2 - 8x + 16 = x^2
144 - 8x + 16 = 0 .... the x^2 terms cancel
160-8x = 0
160 = 8x
8x = 160
x = 160/8
x = 20 is the hypotenuse
x-4 = 20-4 = 16 is the longer leg
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Check:
12^2+16^2 = 144+256 = 400
20^2 = 400
Since 12^2+16^2 = 20^2 is true, this means we have a right triangle with legs of 12 and 16, while the hypotenuse is 20. The answer is confirmed.