Question

Solve by factorising x² + 11x + 30 = 0
dont get think one could someone explain this please.

Answer 1

x = - 6, x = - 5

Explanation:

Given

x² + 11x + 30 = 0

Consider the factors of the constant term (+ 30) which sum to give the coefficient of the x- term (+ 11)

The factors are + 6 and + 5 , since

6 × 5 = 30 and 6 + 5 = 11, then

x² + 11x + 30 = 0

(x + 6)(x + 5) = 0 ← in factored form

Equate each factor to zero and solve for x

x + 6 = 0 ⇒ x = - 6

x + 5 = 0 ⇒ x = - 5

Answer 2

x={-5,-6}

Explanation:

x²+11x+30=0

x²+5x+6x+30=0 (as 5*6=30 and 5+6=11)

x(x+5)+6(x+5)=0

(x+5)(x+6)=0

so

x+5=0

x+6=0

therefore

x=-5

x=-6