Answer:
5
Step-by-step explanation:
2.63x5 = 15.78
4mins---->12 cars
6mins---->(6*12/4)=18
4mins---->12
5mins---->(5*12/4)=15
And so on
How to solve:
( x , y )
Plug the values in to the equation and solve
-3x+5y=2x+3y
(2,4) plugged in would be
-3(2)+5(4)=2(2)+3(4)
All you have to do is solve this and if the two sides are not equal(like 4=20), then it is not a solution. Just plug in (3,3) next.
Hope this helped!!!
Answer:
14. x=-2.5, y = -7
15. x=28 y = -20
Step-by-step explanation:
14. Let's solve this system by elimination. Multiply the first equation by -1.
-1*(4x-y)= -1*(- 3)
-4x +y = 3
Then add this to the second equation.
-4x+y = 3
6x-y= - 8
--------------
2x = -5
Divide each side by 2
x = -2.5
We still need to find y
-4x+y =3
-4(-2.5) + y =3
10 +y =3
Subtract 10 from each side.
y = 3-10
y = -7
15.I will again use elimination to solve this system, because using substitution will give me fractions which are harder to work with. I will elimiate the y variable. Multiply the first equation by 11
11(
5x+6y)= 11*20
55x+66y = 220
Multiply the second equation by -6
-6(9x+11y)=32*(-6)
-54x-66y = -192
Add the modified equations together.
55x+66y = 220
-54x-66y = -192
---------------------------
x = 28
We still need to solve for y
5x+6y = 20
5*28 + 6y =20
140 + 6y = 20
Subtract 140 from each side
6y = -120
Divide by 6
y = -20
