Question

1. Factorise : x2 + 11x +18​

Answer 1

Answer:

Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

x^2-(11*x-18)=0

Step by step solution :

STEP

1

:

Trying to factor by splitting the middle term

1.1 Factoring x2-11x+18

The first term is, x2 its coefficient is 1 .

The middle term is, -11x its coefficient is -11 .

The last term, "the constant", is +18

Step-1 : Multiply the coefficient of the first term by the constant 1 • 18 = 18

Step-2 : Find two factors of 18 whose sum equals the coefficient of the middle term, which is -11 .

-18 + -1 = -19

-9 + -2 = -11 That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -9 and -2

x2 - 9x - 2x - 18

Equation at end of step 1:

(x - 2) • (x - 9) = 0

STEP

2

:

Theory - Roots of a product

2.1 A product of several terms equals zero.

When a product of two or more terms equals zero, then at least one of the terms must be zero.

We shall now solve each term = 0 separately

In other words, we are going to solve as many equations as there are terms in the product

Any solution of term = 0 solves product = 0 as well.

Solving a Single Variable Equation:

2.2 Solve : x-2 = 0

Add 2 to both sides of the equation :

x = 2

Solving a Single Variable Equation:

2.3 Solve : x-9 = 0

Add 9 to both sides of the equation :

x = 9

Supplement : Solving Quadratic Equation

Parabola, Graphing Vertex and X-Intercepts :

Root plot for : y = x2-11x+18

Axis of Symmetry (dashed) {x}={ 5.50}

Vertex at {x,y} = { 5.50,-12.25}

x -Intercepts (Roots) :

Root 1 at {x,y} = { 2.00, 0.00}

Root 2 at {x,y} = { 9.00, 0.00}

Step-by-step explanation:

1. x = 9

2. x = 2

This is your answer

Answer 2

Hello dear☺

See solution: -

a ---> 1

b----->11

c------> 18

$x {}^{2} + 11x + 18 = 0 \\ x {}^{2} + 2x + 9x + 18 = 0 \\ x(x + 2) + 9(x + 2) = 0 \\ (x + 9)(x + 2) =0$

$(x + 9) = 0 \\ x = - 9$

$x + 2 = 0 \\ x = - 2$

ok marks the brainlist☺❤