Explain how to use a number line to show that opposite quantities combine to make 0

46.2+112.3

step-by-step explanation:

answer: bea's uncle is 25 years old.

step-by-step explanation:

given the equation , we can say that the variable "x" represents the age of bea's uncle. then to find his age, we need to solve for "x":

we must add 15 to both sides of the equation:

now we need to divide both sides of the equation by 3:

therefore, we can conclude that bea's uncle is 25 years old.

so mark-up is 0.4 multiplied by 180 = 72

the one where 1 and 2 are directly across from each other.  

see image