Answer:
-8x+12
Explanation:
the perimeter is equal to 2l+2w
so the perimeter would be 2(-5x+10)+2(x-4)
so we just have to use distributive property to simplify it
2x-5x=-10x 2x10=20 2xx=2x 2x-4=-8
now we have -10x+20+2x-8
the last step would be to combine like terms
-10x+2x=-8x
20-8=12
so the expression would be -8x+12
hope this helps :)