# Aim: How to solve verbal problems with quadratic equations?

## Presentation on theme: "Aim: How to solve verbal problems with quadratic equations?"— Presentation transcript:

Aim: How to solve verbal problems with quadratic equations?
Do Now: The square of a number decreased by 4 times the number equals 21. Find the number.

The square of a number decreased by 4 times the number equals 21. Find the number. Let n equal the number The square of the number - n2 Four times a number - 4n n2 - 4n = 21 1. Put in standard form n2 - 4n - 21 = 0 2. Factor (n - 7)(n + 3) = 0 3. Set each factor equal to zero and solve. n + 3 = 0 n = -3 n - 7 = 0 n = 7

The product of two consecutive, positive, even integers is 80. Find the integers. 8 n - first of the consecutive, positive, even integers 10 n + 2 the next consecutive, positive, even integer n(n + 2) = 80 1. Put in standard form n2 + 2n = 80 n2 + 2n - 80 = 0 2. Factor (n + 10)(n - 8) = 0 3. Set each factor equal to zero and solve. n - 8 = 0 n = 8 n + 10 = 0 n = -10