Question

Analyze the diagram below and complete the instructions that follow. Find the value of x. A. 2 B. 4 C. 6 D. 8

Answer 1

B. 4.

Explanation:

By the Pythagoras Theorem:

(√20)^2 = x^2 + (x - 2)^2

20 = x^2 + x^2 - 4x + 4

2x^2 - 4x - 16 = 0

x^2 - 2x - 8 = 0

(x - 4)(x + 2) = 0

x = -2, 4.

x cannot be negative so x = 4 is the answer.

Answer 2

B

Explanation:

(x-2)^2+x^2=20

2x^2-4x+4=20

2x^2-4x-16=0