Multiply first equation by 8,
24x + 40y = 352
Multiply second equation by 3,
24x - 21y = -75
Now, subtract second from 1st,
61y = 427
y = 427/61
y = 7
Substitute it in very first equation,
3x + 5(7) = 44
3x = 44 - 35
x = 9 / 3
x =3
In short, Your Answer would be Option D) (3, 7)
Hope this helps!
Answer:
40 students
Step-by-step explanation:
In this problem, one is given the ratio ( 8 : 3 ), since a ratio is another way of writing a fraction one can rewrite it as;
(8) represent the number of students who want to learn about magnets, and (3) represents the number of students who want to learn about magic tricks.
In the problem, it is also given that 25 more students wanted to learn about magnets compared to magic tricks. If one uses the parameter (x) to represent the factor by which the fraction
is reduced, then one can get the equation;
8x = 3x + 25
Use inverse operations to solve,
8x = 3x + 25
-3x
5x = 25
/5
x = 5
Substitute back in to find out how many students want to learn about magnets,
8x
= 8(5)
= 40
Answer: Add 11 to the other side of the equation, giving you 81. Then, since x is square you are going to need to square root both sides (
this symbol). When you do that, you should get what x is! Let me know if you still need help!
Given:
unit rate: 20km/h
Speed = distance / time
20kmh = 30km / time
time = 20kmh / 30km
time = 2/3 hrs or 40 minutes
2/3 hrs * 60mins/hr = (2*60)/3 = 120/3 = 40 minutes