a + b = 14
a * b = 40
a + b = 14 Subtract a to both sides
a + b - a = 14 - a
b = 14 - a
a * b = 40
a * ( 14 - a ) = 40
14 a - a ^ 2 = 40
- a ^ 2 + 14 a = 40 Subtract 40 to both sides
- a ^ 2 + 14 a - 40 = 40 - 40
- a ^ 2 + 14 a - 40 = 0 Multiply both sides by - 1
a ^ 2 - 14 a + 40 = 0
The solutions are:
a = 4 and a = 10
For a = 10
b = 14 - a = 14 - 10 = 4
For a = 4
b = 14 - 4 = 10
The numbers are:
4 and 10
4 + 10 = 14
4 * 10 = 40
The sum of 2 numbers is 14. The product is 40. What is the largest of numbers?
2 answers
one number ---- x , the larger
the other --- 14-x
x(14-x) = 40
14x - x^2 = 40
x^2 - 14x + 40 = 0
(x-10)(x-4) = 0
x = 10 or x = 4
the two numbers are 10 and 4.
the other --- 14-x
x(14-x) = 40
14x - x^2 = 40
x^2 - 14x + 40 = 0
(x-10)(x-4) = 0
x = 10 or x = 4
the two numbers are 10 and 4.