X + 3y = 7
x = -3y + 7
2x + 4y = 8
2(-3y + 7) + 4y = 8
-6y + 14 + 4y = 8
-2y = 8 - 14
-2y = - 6
y = -6/-2
y = 3
x + 3y = 7
x + 3(3) = 7
x + 9 = 7
x = 7 - 9
x = -2
solution is (-2,3)
Take the vector u = <ux, uy> = <4, 3>.
Find the magnitude of u:
||u|| = sqrt[ (ux)^2 + (uy)^2]
||u|| = sqrt[ 4^2 + 3^2 ]
||u|| = sqrt[ 16 + 9 ]
||u|| = sqrt[ 25 ]
||u|| = 5
To find the unit vector in the direction of u, and also with the same sign, just divide each coordinate of u by ||u||. So the vector you are looking for is
u/||u||
u * (1/||u||)
= <4, 3> * (1/5)
= <4/5, 3/5>
and there it is.
Writing it in component form:
= (4/5) * i + (3/5) * j
I hope this helps. =)
Answer:
6 miles per hour
Step-by-step explanation:
speed = distance/time
speed = 1/2÷1/12 which is the same as
1/2 x 12/1 = 6
6 miles per hour.
or ou could change the 1/2 to become 0.5
and the 1/12 to become 0.083333333
and divide 0.5 ÷ 0.083333333 = 6.000000024
rounded to one decima place become 6.0
6 miles per hour
