12^2 - 11^2
= 144 - 121
= 23
square root (23) = 4.79 = 4.8
answer
C. 4.8
I one is 8x<24 and -8≤2x-4
Hence x <24/8 =3 and -4≤2x: divide by positive 2 to get -2≤x
Hence solution is -2≤x<3
Therefore c is the correct matching for 1.
2) 5x-2>13 or -4x≥8
i.e. 5x>15 or x≤8/(-4) = -2 (since dividing by negative inequality reverses)
Or x>3 or x ≤-2
Hence solution is two regions to the right of 3 excluding 3 and left of -2 including -2.
Graph b is the correct match.
3) -25≤9x+2<20
Subtract 2
-27≤9x<18: Now divide by positive 9
-3≤x<2
Hence graph is the region between -3 and 2 including only -3.
Graph a is correct matching for question 3.
