Question

Find the solution(s) for x in the equation below.x^2 - 9x + 20 = 0

Answer 1

0

Explanation:

Solve the equation x^2-9x+20=0. First, we need to factorise the equation on the left hand side, this can be done by finding two numbers that add together to make the 'b' coefficient (-9) and multiply to make the 'c' coefficient (20). This will give -5 and -4. Therefore, (x-5)(x-4)=0.

Answer 2

x = 4, x = 5

Explanation:

Given

x² - 9x + 20 = 0

Consider the factors of the constant term (+ 20) which sum to give the coefficient of the x- term (- 9)

The factors are - 4 and - 5, since

- 4 × - 5 = + 20 and - 4 - 5 = - 9, thus

(x - 4)(x - 5) = 0

Equate each factor to zero and solve for x

x - 4 = 0 ⇒ x = 4

x - 5 = 0 ⇒ x = 5