Answer:
a) x = -10
b) x = 7
Explanation:
a)
2(x+3) = x - 4
==> distribute the 2
2x + 6 = x - 4
==> add 4 to both sides
2x + 10 = x
==> subtract 2x from both sides
10 = -x
==> divide both sides by -1
x = -10
b)
4(5x - 2) = 2(9x + 3)
==> distribute the 4 and 2
20x - 8 = 18x + 6
==> add 8 to both sides
20x = 18x + 14
==> subtract 18x from both sides
2x = 14
==> divide both sides by 2
x = 7