Question 1003824
The sum of the present ages of Joey and his mother is 46 years.
j + m = 46
 In 4 years, Joey will be one half as old as his mother at that time.
j + 4 = {{{1/2}}}(m + 4)
multiply both sides by 2
2(j+4) = m + 4
2j + 8 = m + 4
2j - m = 4 - 8
2j - m = -4
:
Use elimination on these two equation
j + m = 46
2j - m = -4
--------------addition eliminates m, find j
3j = 42
j = 42/3
j = 14 yrs is Joey
:
Find Mom's age
14 + m = 46
m = 46 - 14
m = 32 yrs is Mom's age
:
:
Check that in the statement
"In 4 years, Joey will be one half as old as his mother at that time." 
14 + 4 = {{{1/2}}}(32 + 4)
18 = {{{1/2}}}(36)