109k views
3 votes
Solve x2 − 8x − 20 = 0.

x = 4, x = −5
x = −4, x = 5
x = 2, x = −10
x = −2, x = 10

User Thinking
by
6.9k points

2 Answers

3 votes
The answer to your problem is D) X=-2, X=10 
User Ronze
by
6.7k points
5 votes

Answer: The correct option is (D) x = −2, x = 10.

Step-by-step explanation: We are given to solve the following quadratic equation :


x^2-8x-20=0~~~~~~~~~~~~~~~~~~~~~(i)

We will be using the method of factorization to solve the given quadratic equation.

From equation (i), we have


x^2-8x-20=0\\\\\Rightarrow x^2-10x+2x-20=0\\\\\Rightarrow x(x-10)+2(x-10)=0\\\\\Rightarrow (x+2)(x-10)=0\\\\\Rightarrow x+2=0,~~~x-10=0\\\\\Rightarrow x=-2,~10.

Thus, the required solution is

x = −2, x = 10.

Hence, option (D) is CORRECT.

User Ben Hamilton
by
7.0k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.