Problema Solution
two numbers multiply together to make -15
they add together to make 2
What are the two numbers?
Answer provided by our tutors
let 'x' and 'y' be the numbers
two numbers multiply together to make -15
x*y = -15
they add together to make 2
x + y = 2 = > y = 2 - x
lets plug y = 2 - x into x*y = -15 we get
x(2-x) = - 15
by solving the above quadratic equation we find two roots
x1 = 5
x2 = -3
click here to see the step by step solution of the equations
For x = 5, y = 2 - 5 = -3
indeed 5*(-3) = - 15 and 5 + (-3) = 2
one solutions is x = 5, y = -3.
For x = -3, y = 2 - (-3) = 5
indeed (-3)*5 = - 15 and -3 + 5 = 2
second solutions is x = -3, y = 5.