A man of height 2.1 meters walk away from a 5-meter lamppost at a speed of 1.5 m/s. Find the rate at which his shadow is increasing in length

Question

anonymous · Answer

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anonymous · Answer

By similar triangle with y is the shadow length:
    y/ 2.1 = ( x + y ) / 5

anonymous · Answer

@heyheyhey111 Questions?

anonymous · Answer

uhm let me work it out thanks I will ask again if I have questions

anonymous · Answer

Okay uhm, how do I solve for just x, or just y? I tried to solve it out and I got y =2.1x / 2.9

anonymous · Answer

actually would x be equal to the 1.5?

anonymous · Answer

Yes haha I got it right, kind of talking to myself but you helped me with the triangles thanks!

anonymous · Answer

y =2.1x / 2.9
"Find the rate at which his shadow is increasing in length"  at x' = 1.5 m/s. 
-> y' = ....
Have you got to y' ?