Answer:
Teachers are idiots that's why :)
Here is one way to solve for x.
Step 1) 2x^2-7=9
Step 2) 2x^2-7+7=9+7
Step 3) 2x^2=16
Step 4) (2x^2)/2=16/2
Step 5) x^2=8
Step 6) sqrt(x^2)=sqrt(8)
Step 7) |x|=sqrt(8)
Step 8) x=sqrt(8) or x=-sqrt(8)
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Below are explanations/reasons to each of the steps above.
Step 1) Original equation
Step 2) Add 7 to both sides
Step 3) Combine like terms
Step 4) Divide both sides by 2
Step 5) Simplify
Step 6) Apply the square root to both sides. The notation "sqrt" is shorthand for "square root"
Step 7) Use the rule that sqrt(x^2) = |x| for all real numbers x
Step 8) Use the rule that if |x| = k then x = k or x = -k for some fixed number k.
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The two solutions are
x = sqrt(8) or x = -sqrt(8)
Step-by-step explanation:
so, if I understand this correctly, the original square had a side length of 8 m.
now we transform this square into one with side length 1/4×8 = 8/4 = 2 m.
and the questions are what are the perimeter and the area of that new (smaller) square ?
the perimeter of a square is
4× side length = 4×2 = 8 m
the area of a square is
side length ² = 2² = 4 m²
I believe that answer is B. (The second one)
Hope this helped !!
Answer:
AB = 9
Step-by-step explanation:
The perpendicular bisector divides Δ ABC into 2 congruent triangles, that is
Δ ABD ≅ Δ ACD , then
AB = AC = 9