anonymous one year ago City A and City B had two different temperatures on a particular day. On that day, four times the temperature of City A was 8° C more than 3 times the temperature of City B. The temperature of City A minus twice the temperature of City B was −3° C. What was the temperature of City A and City B on that day?

1. anonymous

City A was 5° C, and City B was 4° C. City A was 3° C, and City B was −1° C. City A was 8° C, and City B was −3° C. City A was 5° C, and City B was −5° C

2. anonymous

would it be the second answer

3. welshfella

let temperature in CitY A be x and temperature in City B be y

4. welshfella

4x = 3x + 8 x - 2y = -3

5. anonymous

wait so why would it be 4x instead of 8x

6. welshfella

you can find which option is correct by plugging in the given values and see which ones fit

7. welshfella

4 times x = 4x

8. welshfella

four times the temperature of city A = 4 times x = 4x

9. anonymous

ok thank you that makes alot more sense

10. welshfella

you can solve the system of equations or as I said earlier you can plug in the values in the options to see which fit.

11. anonymous

ill plug in the values

12. anonymous

4(3)=3(3)+8

13. welshfella

first try x=5 and y = 4 4(5) = 3(4) + 8 20 = 12 + 8 - those fit

14. welshfella

now plug same values into x - 2y = -3

15. anonymous

ok gotcha

16. anonymous

(5)-2(4)=-3

17. anonymous

5-8=-3 -3=-3

18. anonymous

it works

19. welshfella

right

20. anonymous

thanks