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)
The answer is 0.444 repeating.
-2*4=-8
-8 is the correct answer
Answer:
x + y = 125
3.50x + 2.25y = 347.50
53 rolls
Step-by-step explanation:
System of equations
so basically if we say that rolls are represented by x and wrapping paper is represented by y, we can say x plus y is 125 because there are a total of 125 rolls and packages. if each roll is 3.50 and each package is 2.25, we can just put each number in front of the corresponding variable to show that each one is worth that amount, and they total to 347.50. then you have to solve the system of equations. so if you solve for x in the first equation, x = 125 - y. so plug that in to the next equation, 3.50(125 - y) + 2.25y = 347.50. solve for y and you get 72.
but y is the number of packages, and we want the number of rolls. there are 125 rolls and packages, so 125 minus the 72 packages and you get 53 rolls
Answer: she is 35.3 feet from the tree.
Step-by-step explanation:
Assuming her line of sight to the top of the tree is a straight line, then a right angle triangle is formed. The height of the tree, h represents the opposite side of the right angle triangle. Her distance, h from the tree represents the adjacent side of the right angle triangle. To determine h, we would apply the tangent trigonometric ratio.
Tan θ = opposite side/adjacent side. Therefore,
Tan 27 = 18/h
h = 18/tan27 = 18/0.51
h = 35.3 feet
