## tej18 Group Title [6.03] What is the value of the y variable in the solution to the following system of equations? 2x + y = 5 x + 3y = 0 −1 1 3 −3 2 years ago 2 years ago

1. tej18 Group Title

i really need help :0

2. abayomi12 Group Title

Let x = xylophones and y = yachts. Fred is buying xylophones and yachts. He does not pay attention to how much each costs, rather he just pays for all of them in one go. When he visits the shop on Monday, he buys two xylophones and one yacht for a total price of $9. He then thanks the salesman and goes home. The next day he buys three xylophones and four yachts for a total price of$26. Fred is now deeply curious as to how much his xylophones and yachts would have cost him individually, so he sets up a set of simultaneous equations in an attempt to find an answer to the ultimate question... 2x + y = 9 3x + 4y = 26 Transpose equation 1 and substitute into 2: y = 9 - 2x 3x + 4(9 - 2x) = 26 3x + 36 - 8x = 26 -5x = -10 x = 2 y = 9 - 4 y = 5 So it turns out that xylophones cost $2 each and yachts cost$5 each. ANSWERS: 3. Parallel 4. -6 + x 8. -1 9. (9, -1) 10. Multiply the first equation by -2 11. 42 12. 22.95 + 0.08m = 27.95 + 0.06m 13. 70 14. d = 3(r – 30) and d = 2(r + 30) 15. 3 hours 16. (5, 1) 17. Green area: 2x + y > 2 and x − y < 6 Yellow area: 2x + y > 2 and x − y > 6 18. Answer shown in part 2 (very long answer)

3. mathslover Group Title

$\large{\color{red}{2x+y=5}}$ $\large{\color{blue}{\textbf{Solve for x in this eqn}}}$

4. mathslover Group Title

@tej18 what do you get after solving for x in 2x+y=5

5. sauravshakya Group Title

OMG......... what is that @abayomi12

6. tej18 Group Title

ikr! @sauravshakya

7. tej18 Group Title

i dont get it @mathslover

8. mathslover Group Title

2x+y=5 2x=5-y solve for x

9. tej18 Group Title

ohh

10. abayomi12 Group Title

teji u still don't get the answer that all the answer i just solved there

11. tej18 Group Title

@mathslover so x= 5/2 - y/2??

12. mathslover Group Title

x=(5-y)/2 put this in 2nd eqn

13. mathslover Group Title

14. tej18 Group Title

i m confused @mathslover

15. mathslover Group Title

$\large{x=\frac{5-y}{2}}$ $\large{x+3y=0}$ $\large{\frac{5-y}{2}+3y=0}$ $\large{\frac{5-y+2y}{2}=0}$ $\large{5+y=0}$

16. mathslover Group Title

oops sorry : $\large{\frac{5-y+6y}{2}=0}$ $\large{5+5y=0}$

17. tej18 Group Title

so y=0? @mathslover

18. tej18 Group Title

@mathslover

19. Kaederfds Group Title

i got y = (-1)

20. tej18 Group Title

oh kk thanks! @Kaederfds

21. Sulli_lim Group Title

Answer: -1 2x+y=5 x+3y=0 So, x=-3y Substitute x=-3y into 2x+y=5 2(-3y)+y=5 -6y+y=5 -5y=5 y=-1

22. mathslover Group Title

5y=-5 y=-1 @tej18