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2 years ago

Hi, please help me out :)) thank you

Mathematics

2 answers:

ra1l [238]2 years ago

7 0

Answer:

d = 32

Step-by-step explanation:

$\sqrt{7d-1} -4+4=11+4$

$\sqrt{7d-1} =15$

$7d+1=15 *15$

$7d+1=225$

$7d=225-1$

$7d=224$

$d=\frac{224}{7}$

$d=32$

r-ruslan [8.4K]2 years ago

4 0

Answer:

d =32

Step-by-step explanation:

$\sqrt{7d+1}-4=11\\\\\mathrm{Add\:}4\mathrm{\:to\:both\:sides}\\\sqrt{7d+1}-4+4=11+4\\\\Simplify\\\sqrt{7d+1}=15\\\\\mathrm{Square\:both\:sides}:\quad 7d+1=225\\7d+1=225\\\\\mathrm{Solve\:}\:7d+1=225:\\\quad d=32$

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3 years ago

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Hence, the trains will be 1520 km apart at 2:40 pm for the cargo train and at 4:40 pm for the passenger train.

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I hope it helps you!

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