Answer:
Mary-15
Joan-9
Step-by-step explanation:
1) create an equation with the information given:
x•(x+6)=135
2) using this create a quadratic equation by distributing and getting all the terms to one side:
y=x²+6x-135
3) finally use the quadratic formula, ((-b)±√(b²-(4•a•c)))/(2•a)
4) using this you will find the value for Joan's age. Add six to Joan's age to find Mary's
5) You can check your answer by multiplying them to see if they equal 135.
