Firstly Bernard = x
A) lets focus on Therese first. Bernard id two years older than her so for Therese’s equation in terms of x it would be x+2. Now for Josephine Bernard is 4 years younger than HER so it would be 4-x.
B) The mother is the PRODUCT of the sisters’ ages so (multiplication)
It would be like this: (x+2)(4-x)= 40 This is all in terms of x.
Solving for the equation (using distributive property) we get:
4x-x+8-2x=40
(Reorganize to group like terms, remember to go in order from the numeral numbers with variables, to variables only then numbers only): 4x-2x-x+8=40 (now combine like terms and simplify): x+8=40 this is his mom’s age in terms of x
C) HERE we can solve for x:
Isolating x to get the answer we move the 8 to the other side of the equation and it becomes a negative 8 so:
x=40-8
x=32
Therefore Bernard is 32 years old.
Hope this helps!
