We need to know some log properties
1. when the base is not stated, assume that it is base 10 or log₁₀
2.

-log(10^-1)=

answer is D. -1
I’m not 100% sure but isn’t it x2 +xy +y2?
If you need further help on how they got the answer, this equation will take more time, but it will also help you understand these types of problems. Part÷Whole=Percent÷100
Part= X because it is what you are trying to find.
Whole=250 because it is what you are taking the percentage of.
Percent=80
Now you have:
X÷250=80÷100
Set this up in fraction form and cross multiply.
You get:
100x=250×80
250×80=20,000
100x=20,000
X=200
Edited answer: The number is: "- 6" .
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8 (8 + x) = 16 ;
in which "x" represents the number for which to be solved ;
8*8 + 8*x = 16 .
Edit: 64 + 8x = 16 ;
Subtract "64" from each side of the equation:
Edit: 64 + 8x − 64 = 16 <span>− 64 ;
to get: 8x = </span>- 48 ;
Divide EACH SIDE of the equation by "8" ; to isolate "x" on one side of the <span>equation ; and</span> to solve for "x" ;
Edit: 8x / 8 = -48 / 8 ;
Edit: x = - 6 .
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The number is: "- 6" .
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Let us check our answer, by plugging in "-6" for "x" in the original equation:
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8 (8 + x) = 16 ;
→ 8 [8 + (-6) ] =? 16 ?? ;
→ 8 (8 − 6 ) =? 16 ?? ;
→ 8 (2) =? 16 ?? ;
→ 16 = ? 16 ?? Yes!
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<h3>
Answer: 16 square units</h3>
Let x be the height of the parallelogram. Right now it's unknown, but we can solve for it using the pythagorean theorem. Focus on the right triangle. It has legs a = 3 and b = x, with hypotenuse c = 5
a^2 + b^2 = c^2
3^2 + x^2 = 5^2
9 + x^2 = 25
x^2 = 25-9
x^2 = 16
x = sqrt(16)
x = 4
This is a 3-4-5 right triangle.
The height of the parallelogram is 4 units.
We have enough info to find the area of the parallelogram
Area of parallelogram = base*height
Area of parallelogram = 4*4
Area of parallelogram = 16 square units
Coincidentally, the base and height are the same, which isn't always going to be the case. The base is visually shown as the '4' in the diagram. The height is the dashed line, which also happens to be 4 units long.