Sam is 10 years younger than one-half the age of his aunt. Let a represent his aunt’s age. Which algebraic expression can be used to determine Sam’s age if his aunt is 40?

Sam is 10 years old

Step-by-step explanation:

Sam is 10 years old because 20 is half of 40 and 20 subtract 10 is 10

2 over 5

step-by-step explanation:

the 2: 3 ratio is the length of the ac segment to the cb segment total length. this implies that the ratio between segment ac length and segment ab length is 2: 5. point c is 2/5 from a to b, so the required fraction is 2/5.

3< x< 5

step-by-step explanation:

|x - 4| < 1

there are two solutions, one positive and one negative.   remember to flip the inequality when taking the negative solution

x-4 < 1       x-4 > -1

add 4 to each side

x-4+4 < 1+4       x-4+4 > -1+4

x< 5                 x> 3

3< x< 5