please answer 2.) a and b!

1.a. correct
1.b. [tex] \sqrt{121} - \sqrt{9} = 11 - 3 = 8 [/tex]
1.c. correct
1.d. [tex] -\sqrt{36} - \sqrt{100} = -6 - 10 = -16 [/tex]
2.a. 7 - x + 3w - 9
Terms: 7, -x, 3w, -9
Variables: x, w
Coefficients: -1, 3
Constants: 7, -9
2.b. -g + 8k - 3 - 7
Terms: -g, 8k, -3, -7
Variables: g, k
Coefficients: -1, 8
Constants: -3, -7
3.a. correct
3.b. correct
3.c. -5+ 4x = -x
4.a. 4(2x + 3) = 8x + 12
4.b. -2(3x + 4) = -6x - 8
4.c. -5(2x - 3) = -10x + 15