1:number of people in group 3a+4b+x
Number of people in the second group: (3a+4b+x)/2+6 =1.5a+2b+0.5x+6.
Number of people in the third group: [(3a+4b+x)+1.5a+2b+0.5x+6]/3+3 = (4.5a+6b+1.5x+6)/3+3 =1.5a+.
Number of people in the fourth group: 50-(3a+4b+x)-(1.5a+2b+0.5x+6)-(1.5a+2b+0.5x+5).
=39-6a-8b-2x
(it should be expressed by a formula containing a, b and x, right? )
2.
The quadratic of 2 (x- 1/2)+y- 1 =0.
The quadratic of 2 (x- 1/2) is a positive number, and y- 1 is also a positive number, and the sum is 0, so it must all be equal to 0.
therefore
(x- 1/2)=0,X= 1/2=0.5
y- 1=0,y= 1
b =(2 * 0.5)*(2 * 0.5)-3 * 0.5 * 1-(2 * 1)(2 * 1)= 1- 1.5-4 =-4.5
3B-24 = 3 *(4.5)-24 =- 13.5-24 =-37.5
Why is it useless? Did you copy it wrong?
Besides, does "2x squared" mean 2X*2X? Or 2X*X? )