Answer:
x=6
Step-by-step explanation:
x-7=-1 add -1 to other side of the equation
x-6=0 add six to the zero
8. False.
11 and 13 are consecutive prime numbers, but 11 + 13 = 24 and 24 isn't prime.
9. True.
10. True.
11. True
12. False.
13. True.
4x +13 +79+79+ 11x-6 = 360
15x +165 = 360
15x = 195
x =13
QRS = 11(13)-6 = 137
21 mph