Are you looking for the number of cans you and your friend each collected? If yes, here is the solution:
Let x be the number of cans.
4x + 5x = 180
9x = 180
9x/9 = 180/9 (divide both sides of the equation by 9)
x = 20
Now, substitute the values:
4(20) + 5(20) = 180
80 + 100 = 180
180 = 180
Therefore, you collected 80 cans and your friend collected 100 cans.
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)
Answer:
3
Step-by-step explanation:
21.1 should be the correct answer because 4.5% of 2000 is 90