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3 years ago

Jackson’s age was 2/5 of the age he will be 20 years from now 7 years ago. How old is Jackson now?

Mathematics

1 answer:

bonufazy [111]3 years ago

4 0

<h3>The present age of Jackson is 25 years old</h3>

<em><u>Solution:</u></em>

Let the present age of Jackson be "x"

Therefore

Jackson's age 7 years ago = x - 7

And, Jackson's age after 20 years = x + 20

From given question,

Jackson’s age was 2/5 of the age he will be 20 years from now 7 years ago

$\frac{2}{5} \times (x + 20) = x - 7\\\\2(x + 20) = 5(x - 7)\\\\2x + 40 = 5x - 35\\\\5x - 2x = 40 +35\\\\3x = 75\\\\Divide\ both\ sides\ by\ 3\\\\x = 25$

Thus present age of Jackson is 25 years old

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Answer:

See below

Step-by-step explanation:

Here we need to prove that ,

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Where the symbols have their usual meaning.

Now , taking LHS ,

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Substituting the respective values,

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From equation (i) ,

$\sf\longrightarrow\cancel{ \dfrac{h^2}{h^2}}\\$

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I hope this helps.

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2 years ago

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Lina20 [59]

Answer:

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2 years ago

The mean age of a student book club is 14.2 years. A 27-year-old teacher is invited to join the club. How does the teacher’s age

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3 years ago

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Answer:

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Step-by-step explanation:

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b) In this case $u=\sec(2x)$ hence $du=2\tan(2x)\sec(2x)dx$ . We rewrite the integral as $\int 20\tan(2x)\sec^2(2x)dx=\int 10\sec(2x) (2\tan(2x)\sec(2x))dx=\int 10udu=5\frac{u^2}{2}+C=5\sec^2(2x)+C$ .

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zheka24 [161]

Answer:

Step-by-step explanation:

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