make u the subject in x =2u−33u+2
u = 2x+33x−2
u = 2x−33x−2
u = 2x+32−3x
u = 2x+33x+2
Correct answer is C
x =2u−33u+2
cross multiply
x(3u + 2) = 2u - 3
3ux + 2x = 2u - 3
collect like terms of u
2x + 3 = 2u - 3ux
2x+32−3x = u
60°
40°
90°
120°
Correct answer is A
In a polygon with n sides, the sum of the angles =
(n - 2)180, where n = the number of sides.
In our problem, n = k.
So, we have:
(3k - 10)90 = (k - 2)180
270k - 900 = 180k - 360
Simplifying:
90k = 540
k = 6. So, we have a regular hexagon.
Now, each exterior angle = 360/n
We have: 360/6 = 60
Conclusion: Each exterior angle is 60 degrees.
If 4x+2y=16 and 6x-2y=4 , find the value of (y-x).
8
2
4
6
Correct answer is B
Using elimination method:
4x+2y=16 * 6 --> 24x +12y=96 ... eqn iii
6x-2y=4 * 4 --> 24x - 8y = 16 ... eqn iv
Subtract eqn iv from iii
20y = 80
y = 4
Subst. y for 4 in 4x + 2y = 16
--> 4x + 2(4) = 16
--> 4x = 16 - 8
--> 4x = 8
--> x = 2
: The value of (y-x) is 4 - 2 = 2