Answer:
20%
Step-by-step explanation:
So, I would set this up as a proportion-
72 x
90 100
Cross multiply-
100 x 72 = 7200
Divide-
7200/90 = 80
Subtract-
100 - 80 = 20
So, it is a 20% decrease
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 scatter plot has been attached
Answer:
Options C, D & E are true
Step-by-step explanation:
Option A is wrong because from the scatter plot, only four athletes were faster in the second race than in the first one.
Option B is wrong because only 1 athlete had his second race time differing from the first race time by exactly 2 seconds.
Option C is true because exactly 9 of the times for the first race were at least 16 seconds
Option D is true because there are exactly 3 athletes who had the same time in both races
Option E is true because 8 of the times for the second race were less than 17 seconds
Answer:
-10
-I-8I = -8
-(-2) = 4
I-11I = 11
5² = 25
Answer: -10, -8, 4, 11, 25
Answer:
Step-by-step explanation:
Total number of boxes of cookies that Kendal bought to bring to the party is x.
Each box contains 12 cookies. This means that total number of cookies in x boxes would be
12 × x = 12x
She decides to keep two boxes for herself. This means that the total number of cookies that she kept for herself would be
12 × 2 = 24 cookies
She brings 60 cookies to the party.
The equation that can be used to find the number of boxes, x, Kendal bought would be
12x = 24 + 60
12x = 84
x = 84/12 = 7 boxes