Answer:
(-3x - 9) + (4x + 8) = x - 1
Explanation:
This is a problem where you have the expand the brackets first, but in a fairly simple way. It can also be written like this:
y = 1(-3x - 9) + 1(4x+8)
So now expand the brackets by multiplying each term by positive one:
y = -3x - 9 + 4x + 8
In this case, none of the signs changed, and so it looks almost the same. Watch out in other problems if you have to multiply by negative 1, as this can change some things around. But in this case:
y = -3x - 9 + 4x + 8
y = x - 9 + 8 ← combining the x's (-3x + 4x = 1x)
y = x - 1 ← combining the constants (-9 + 8 = -1)
∴ (-3x - 9) + (4x + 8) = x - 1
Hope that helps!