Well 3/4 is 0.75 and 1/2 is 0.50 so 75 - 50 which is .25 so 1/4
The answer is A
We have. x=1, then we substitute that on x+z = 20, to solve for z.
1+z=20
z=20-1
z=19
Then we substitute both values x=1 and z=19 on the other equation.
2x +2y+ z = -12
2*1 + 2y + 19= -12
2y= -12 -19-2
2y= -33
y=-33/2
The product of 6 x 106 = 636