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

Question

options are x square-4y square  .second is 8

Answer 1

Hi, this problem is very easy .it can be put this way

 

Given

 

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

 

it is of the form 

 

(a-b)(a+b)= c

 

where a = x , b= 2y and c=4

As we know

(a-b)(a+b) = a^2 - b^2

 

=> x^2 - (2y)^2 = 4

=> x^2 -4y^2 =4

=> x^2 -4y^2-4 =0 so first option is the right answer

 

Answer 2

This is an interesting problem. I haven't ever quite seen a problem like this.

 

(x-2y)(x+2y)=x^2+2xy-2xy-4y^2=x^2-4^2

 

x^2-4y^2=4 I'm not sure what is being asked for this problem. However, you got one equation with two unknowns.

 

However, if this problem is regarding identifying equations of conics, like parabolas, ellipse, or hyperbolas, then you could rewrite this equation by dividing it by 4.

 

x^2/4-y^2/1=1 Hence, this is an equation of a horizontal hyperbola in which its center is (0,0) and vertices are (2,0) and (-2,0). The vertices come from a^2=4.