## anonymous 5 years ago jane works north of her home. her husband Bob works east. they leave for work at the same time. By the time Jane is 7 miles from home, the distance between them is one mile more than Bobs distance from home. How far from home is bob?

1. anonymous

theorem of pythagoras i would say

2. anonymous

7^2 + (x)^2 = (x+1)^2

3. anonymous

this produces the quadratic $49 + x ^{2} = x^2 + 2x + 1$

4. anonymous

x=24

5. anonymous

6. anonymous

u dont have to in this case as you may simply subtract x^2 from both sides and you get a linear equation in x which is then solved by subtracting one from both sides and dividing by 2

7. anonymous

i dont understand any of it =(

8. anonymous

pythagoras theorem states $hypthenuse^2 = adjacent^2 + opposite^2$

9. anonymous

can u see how their movements form a right angled triangle? draw it for urself

10. anonymous

i thought it was a +b=c

11. anonymous

pythagoras' theorem? no the sides are squared

12. anonymous

i dont understand. sorry

13. anonymous

start by drawing the problem. mark a dot on the page for their home and then take a line 7 north for janes movement.

14. anonymous

now go back to the dot and take a line east for the dot (length doesnt matter) let this line have length x

15. anonymous

ok

16. anonymous

now mark the positions of mary and bob by a dot. now join those two dots and let the length of this new line be x+1 because the question says the distance between them is one more than how far bob is from home

17. anonymous

ok

18. anonymous

now can you see the right angled triangle? the hypothenuse (longest side) has length x+1. apply pythagoras theorem to get $7^2 + (x)^2 = (x+1)^2$

19. anonymous

then solve for x

20. anonymous

7x to the 4th = 2x+2?? i dont know what im doing...im far from help

21. anonymous

i think you are confused between powers of a number and mulitplication$(x+1)^2 = (x+1)(x+1) = x^2 +x + x +1 = x^2 +2x +1$

22. anonymous

which is the right hand side, left hand side is just 49 + x^2

23. anonymous

omg 49 +2x=2x??

24. anonymous

almost $49+x^2 = x^2 + 2x + 1 \rightarrow 49 = 2x +1 \rightarrow 2x=48$

25. anonymous

hm

26. anonymous

verify the steps yourself to make sure u understand

27. anonymous

i dont

28. anonymous

49+x times x=(x+1)(x+1)

29. anonymous

yes correct

30. anonymous

only i dont know how to answer that 49x2=x2+1x+1?

31. anonymous