Answer:
9 years ago.
Step-by-step explanation:
Dotty is 51 years old and Esmerelda is 23 now.
Now, x years ago the age of Dotty was (51 - x) years and the age of Esmerelda was (23 - x) years.
Assume that x years ago Dotty was 3 times Esmerelda's age.
So, we can write the equation as
3(23 - x) = 51 - x
⇒ 69 - 3x = 51 - x
⇒ 69 - 51 = 3x - x
⇒ 18 = 2x
⇒ x = 9 years.
Therefore, 9 years ago Dotty was 3 times Esmerelda's age. (Answer)
Answer:
Numbers that are similar to each other
Examples:
Negative numbers
Positive numbers
Decimals
Fractions
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Equation Given :
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16x² = 121
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Take away 121 from both sides:
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16x² - 121 = 0
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Make each term a perfect square
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(4x)² - (11)² = 0
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Apply algebraic rule : a² - b² = (a + b)(a - b)
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(4x + 11) (4x - 11) = 0
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Apply zero product property :
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4x + 11 = 0 or 4x - 11 = 0
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Solve for x :
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4x = - 11 or 4x = 11
x = -11/4 or x =11/4
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Answer: x = -11/4 or x = 11/4
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Step 1: 1
(((x3) - (2•5x2)) + 29x) - 30 = 0
Step 2 2.1 x3-10x2+29x-30 is not a perfect cube
Step 3 Factoring: x3-10x2+29x-30
Thoughtfully split the expression at hand into groups, each group having two terms :
Group 1: 29x-30
Group 2: -10x2+x3
Pull out from each group separately :
Group 1: (29x-30) • (1)
Group 2: (x-10) • (x2)